diff --git a/lib/doc/Math.lyx b/lib/doc/Math.lyx
index 22a20cff45..a0dbea6fb2 100644
--- a/lib/doc/Math.lyx
+++ b/lib/doc/Math.lyx
@@ -101,6 +101,13 @@
 % used to check for needed LaTeX packages
 \usepackage{ifthen}
 
+% check for package undertilde
+% used for the command \utilde
+\newboolean{undertilde}
+\IfFileExists{undertilde.sty}
+ {\setboolean{undertilde}{true}}
+ {\setboolean{undertilde}{false}}
+
 % check for package eurosym
 % used for the Euro symbol
 \newboolean{eurosym}
@@ -180,7 +187,7 @@
 \use_package mhchem 1
 \use_package stackrel 0
 \use_package stmaryrd 0
-\use_package undertilde 0
+\use_package undertilde 1
 \cite_engine basic
 \cite_engine_type default
 \biblio_style plain
@@ -282,7 +289,7 @@ status open
 \begin_layout Plain Layout
 To export this document to PDF, PS or DVI the LaTeX-packages 
 \series bold
-braket, cancel, eurosym, mathdots, mhchem
+braket, cancel, eurosym, mathdots, mhchem, undertilde
 \series default
  and 
 \series bold
@@ -9535,6 +9542,179 @@ In mathematical text, umlauts and other accented characters can directly
  be inserted.
 \end_layout
 
+\begin_layout Standard
+\begin_inset VSpace bigskip
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+LyX also supports a tilde under the character if the LaTeX-package 
+\series bold
+undertilde
+\series default
+
+\begin_inset Index idx
+status collapsed
+
+\begin_layout Plain Layout
+Packages ! undertilde
+\end_layout
+
+\end_inset
+
+ is installed on your system:
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+ifundertilde 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+The following table will only be displayed when the LaTeX-package 
+\series bold
+undertilde
+\series default
+ is installed.
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\noindent
+\align center
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="2">
+<features rotate="0" tabularvalignment="middle">
+<column alignment="center" valignment="top" width="0pt">
+<column alignment="center" valignment="top" width="0pt">
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Command
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Result
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\backslash
+utilde
+\begin_inset space \textvisiblespace{}
+\end_inset
+
+A
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+\begin_inset Formula $\raisebox{5mm}{}\utilde{A}$
+\end_inset
+
+
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+else 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+The following will be displayed when the LaTeX-package 
+\series bold
+undertilde
+\series default
+ is not installed:
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+You need to install the LaTeX-package 
+\series bold
+undertilde
+\series default
+ to see the rest of this subsection in the output.
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+fi 
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
 \begin_layout Subsection
 Accents for several Characters
 \begin_inset Index idx
diff --git a/lib/doc/de/Math.lyx b/lib/doc/de/Math.lyx
index fbd4ae62b6..1fe535652e 100644
--- a/lib/doc/de/Math.lyx
+++ b/lib/doc/de/Math.lyx
@@ -106,6 +106,13 @@
 % used to check for needed LaTeX packages
 \usepackage{ifthen}
 
+% testen ob das Paket undertilde installiert ist
+% wird benutzt für den Befehl \utilde
+\newboolean{undertilde}
+\IfFileExists{undertilde.sty}
+ {\setboolean{undertilde}{true}}
+ {\setboolean{undertilde}{false}}
+
 % testen ob das Paket eurosym installiert ist
 % wird benutzt für das Euro-Symbol
 \newboolean{eurosym}
@@ -189,7 +196,7 @@
 \use_package mhchem 1
 \use_package stackrel 0
 \use_package stmaryrd 0
-\use_package undertilde 0
+\use_package undertilde 1
 \cite_engine basic
 \cite_engine_type default
 \biblio_style plain
@@ -291,7 +298,7 @@ status open
 Um diese Datei als PDF, PS oder DVI zu exportieren, sollten die LaTeX-Pakete
  
 \series bold
-braket, cancel, eurosym, mathdots, mhchem
+braket, cancel, eurosym, mathdots, mhchem, undertilde
 \series default
  und 
 \series bold
@@ -9558,6 +9565,180 @@ Im mathematischen Textmodus können Umlaute und andere akzentuierten Zeichen
  direkt eingegeben werden.
 \end_layout
 
+\begin_layout Standard
+\begin_inset VSpace bigskip
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+LyX unterstützt auch eine Tilde unter einem Zeichen, wenn das LaTeX-Paket
+ 
+\series bold
+undertilde
+\series default
+
+\begin_inset Index idx
+status collapsed
+
+\begin_layout Plain Layout
+Pakete ! undertilde
+\end_layout
+
+\end_inset
+
+ auf Ihrem System installiert ist:
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+ifundertilde 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+Die folgende Tabelle erscheint nur im Ausdruck wenn das LaTeX-Paket 
+\series bold
+undertilde
+\series default
+ installiert ist:
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\noindent
+\align center
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="2">
+<features rotate="0" tabularvalignment="middle">
+<column alignment="center" valignment="top" width="0pt">
+<column alignment="center" valignment="top" width="0pt">
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Befehl
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Ergebnis
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\backslash
+utilde
+\begin_inset space \textvisiblespace{}
+\end_inset
+
+A
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+\begin_inset Formula $\raisebox{5mm}{}\utilde{A}$
+\end_inset
+
+
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+else 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+Folgendes erscheint im Ausdruck wenn das LaTeX-Paket 
+\series bold
+undertilde
+\series default
+ nicht installiert ist:
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+Das LaTeX-Paket 
+\series bold
+undertilde 
+\series default
+muss installiert sein, um den Rest dieses Abschnitts im Ausdruck zu sehen.
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+fi 
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
 \begin_layout Subsection
 Akzente für mehrere Zeichen
 \begin_inset Index idx
diff --git a/lib/doc/es/Math.lyx b/lib/doc/es/Math.lyx
index f47a52a7f6..cafeb4b9b2 100644
--- a/lib/doc/es/Math.lyx
+++ b/lib/doc/es/Math.lyx
@@ -102,6 +102,13 @@
 % used to check for needed LaTeX packages
 \usepackage{ifthen}
 
+% check for package undertilde
+% used for the command \utilde
+\newboolean{undertilde}
+\IfFileExists{undertilde.sty}
+ {\setboolean{undertilde}{true}}
+ {\setboolean{undertilde}{false}}
+
 % check for package eurosym
 % used for the Euro symbol
 \newboolean{eurosym}
@@ -181,7 +188,7 @@
 \use_package mhchem 1
 \use_package stackrel 0
 \use_package stmaryrd 0
-\use_package undertilde 0
+\use_package undertilde 1
 \cite_engine basic
 \cite_engine_type default
 \biblio_style plain
@@ -284,7 +291,7 @@ status open
 Para exportar este documento a PDF, PS o DVI deberían estar instalados los
  paquetes LaTeX 
 \series bold
-braket, cancel, eurosym, mathdots, mhchem
+braket, cancel, eurosym, mathdots, mhchem, undertilde
 \series default
  y 
 \series bold
@@ -9644,6 +9651,185 @@ cursiva o negrita.
 En texto matemático, la diéresis y otros acentos pueden insertarse directamente.
 \end_layout
 
+\begin_layout Standard
+\begin_inset VSpace bigskip
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+LyX also supports a tilde under the character if the LaTeX-package
+\lang spanish
+ 
+\series bold
+undertilde
+\series default
+
+\begin_inset Index idx
+status collapsed
+
+\begin_layout Plain Layout
+Paquetes ! undertilde
+\end_layout
+
+\end_inset
+
+ 
+\lang english
+is installed on your system:
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+ifundertilde 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+El cuadro siguiente sólo se mostrará en la salida si el paquete LaTeX 
+\series bold
+undertilde
+\series default
+ está instalado.
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\noindent
+\align center
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="2">
+<features rotate="0" tabularvalignment="middle">
+<column alignment="center" valignment="top" width="0pt">
+<column alignment="center" valignment="top" width="0pt">
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Comando
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Resultado
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\backslash
+utilde
+\begin_inset space \textvisiblespace{}
+\end_inset
+
+A
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+\begin_inset Formula $\raisebox{5mm}{}\utilde{A}$
+\end_inset
+
+
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+else
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+Lo que sigue se verá en la salida si el paquete LaTeX 
+\series bold
+undertilde
+\series default
+ no está instalado:
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+Debes instalar el paquete LaTeX 
+\series bold
+undertilde
+\series default
+ para ver en la salida el resto de esta subsección.
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+fi
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
 \begin_layout Subsection
 Acentos para varios caracteres
 \begin_inset Index idx
diff --git a/lib/doc/fr/Math.lyx b/lib/doc/fr/Math.lyx
index 7c8e258ad2..b0994de2b9 100644
--- a/lib/doc/fr/Math.lyx
+++ b/lib/doc/fr/Math.lyx
@@ -102,6 +102,13 @@
 % used to check for needed LaTeX packages
 \usepackage{ifthen}
 
+% check for package undertilde
+% used for the command \utilde
+\newboolean{undertilde}
+\IfFileExists{undertilde.sty}
+ {\setboolean{undertilde}{true}}
+ {\setboolean{undertilde}{false}}
+
 % check for package eurosym
 % used for the Euro symbol
 \newboolean{eurosym}
@@ -184,7 +191,7 @@
 \use_package mhchem 1
 \use_package stackrel 0
 \use_package stmaryrd 0
-\use_package undertilde 0
+\use_package undertilde 1
 \cite_engine basic
 \cite_engine_type default
 \biblio_style plain
@@ -297,7 +304,7 @@ status open
 Pour pouvoir exporter ce document en PDF, PS, ou DVI les paquetages LaTeX
  
 \series bold
-braket, cancel, eurosym, mathdots, mhchem
+braket, cancel, eurosym, mathdots, mhchem, undertilde
 \series default
  et 
 \series bold
@@ -9520,6 +9527,185 @@ En texte mathématique, les trémas et autres caractères accentués peuvent
  être insérés directement.
 \end_layout
 
+\begin_layout Standard
+\begin_inset VSpace bigskip
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+LyX also supports a tilde under the character if the LaTeX-package
+\lang french
+ 
+\series bold
+undertilde
+\series default
+
+\begin_inset Index idx
+status collapsed
+
+\begin_layout Plain Layout
+Paquetages ! undertilde
+\end_layout
+
+\end_inset
+
+ 
+\lang english
+is installed on your system:
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+ifundertilde 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+Ce qui suit ne sera affiché que si le paquetage LaTeX 
+\series bold
+undertilde
+\series default
+ est installé:
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\noindent
+\align center
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="2">
+<features rotate="0" tabularvalignment="middle">
+<column alignment="center" valignment="top" width="0pt">
+<column alignment="center" valignment="top" width="0pt">
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Commande
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+Résultat
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\backslash
+utilde
+\begin_inset space \textvisiblespace{}
+\end_inset
+
+A
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+\begin_inset Formula $\raisebox{5mm}{}\utilde{A}$
+\end_inset
+
+
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+else 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+Ce qui suit sera affiché si la paquetage LaTeX 
+\series bold
+undertilde
+\series default
+ n'est pas installé:
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+Vous avez besoin du paquetage LaTeX 
+\series bold
+undertilde
+\series default
+ pour voir le reste de cette sous section dans la sortie finale.
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+fi 
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
 \begin_layout Subsection
 Accents pour plusieurs caractères
 \begin_inset Index idx
diff --git a/lib/doc/ja/Math.lyx b/lib/doc/ja/Math.lyx
index 90b4a62158..c99daa0a88 100644
--- a/lib/doc/ja/Math.lyx
+++ b/lib/doc/ja/Math.lyx
@@ -110,6 +110,13 @@
 % used to check for needed LaTeX packages
 \usepackage{ifthen}
 
+% check for package undertilde
+% used for the command \utilde
+\newboolean{undertilde}
+\IfFileExists{undertilde.sty}
+ {\setboolean{undertilde}{true}}
+ {\setboolean{undertilde}{false}}
+
 % check for package eurosym
 % used for the Euro symbol
 \newboolean{eurosym}
@@ -221,7 +228,7 @@ End
 \use_package mhchem 1
 \use_package stackrel 0
 \use_package stmaryrd 0
-\use_package undertilde 0
+\use_package undertilde 1
 \cite_engine basic
 \cite_engine_type default
 \biblio_style plain
@@ -345,6 +352,10 @@ mhchem
 \series default
 ・
 \series bold
+undertilde
+\series default
+・
+\series bold
 was
 \series default
 が導入されている必要があります。これらが導入されていなくても文書はエクスポートできますが、パッケージを必要とする節は出力には現れません。また、
@@ -9567,6 +9578,185 @@ ddot
 ウムラウトと他のアクセント付き文字は、数式中テキストに直接入れることができます。
 \end_layout
 
+\begin_layout Standard
+\begin_inset VSpace bigskip
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+LyX also supports a tilde under the character if the LaTeX-package
+\lang japanese
+ 
+\series bold
+undertilde
+\series default
+
+\begin_inset Index idx
+status collapsed
+
+\begin_layout Plain Layout
+ぱっけーじ@パッケージ ! upgreek
+\end_layout
+
+\end_inset
+
+ 
+\lang english
+is installed on your system:
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+ifundertilde 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+以下の表は、
+\series bold
+undertilde
+\series default
+ LaTeXパッケージが導入済みのときのみ表示されます。
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\noindent
+\align center
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="2">
+<features rotate="0" tabularvalignment="middle">
+<column alignment="center" valignment="top" width="0pt">
+<column alignment="center" valignment="top" width="0pt">
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+コマンド
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+出力
+\end_layout
+
+\end_inset
+</cell>
+</row>
+<row>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+
+\backslash
+utilde
+\begin_inset space \textvisiblespace{}
+\end_inset
+
+A
+\end_layout
+
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\begin_layout Plain Layout
+\begin_inset Formula $\raisebox{5mm}{}\utilde{A}$
+\end_inset
+
+
+\end_layout
+
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+else 
+\end_layout
+
+\end_inset
+
+
+\begin_inset Note Note
+status open
+
+\begin_layout Plain Layout
+以下は、
+\series bold
+undertilde
+\series default
+ LaTeXパッケージが導入されていないときのみ表示されます。
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+この小節のすべてを出力で見るには、
+\series bold
+undertilde
+\series default
+ LaTeXパッケージを導入する必要があります。
+\end_layout
+
+\begin_layout Standard
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+
+\backslash
+fi 
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
 \begin_layout Subsection
 複数の文字に付けるアクセント
 \begin_inset Index idx