diff --git a/src/frontends/qt4/GuiSpellchecker.cpp b/src/frontends/qt4/GuiSpellchecker.cpp
index da8cca1ad3..5dbdbbb0b0 100644
--- a/src/frontends/qt4/GuiSpellchecker.cpp
+++ b/src/frontends/qt4/GuiSpellchecker.cpp
@@ -315,8 +315,13 @@ void SpellcheckerWidget::on_replacePB_clicked()
 		return;
 	docstring const textfield = qstring_to_ucs4(d->ui.wordED->text());
 	docstring const replacement = qstring_to_ucs4(d->ui.replaceCO->currentText());
-	docstring const datastring = replace2string(replacement, textfield,
-		true, true, false, false);
+	docstring const datastring = 
+		replace2string(replacement, textfield,
+			true,   // case sensitive
+			true,   // match word
+			false,  // all words
+			true,   // forward
+			false); // find next
 
 	LYXERR(Debug::GUI, "Replace (" << replacement << ")");
 	dispatch(FuncRequest(LFUN_WORD_REPLACE, datastring));
@@ -332,8 +337,13 @@ void SpellcheckerWidget::on_replaceAllPB_clicked()
 		return;
 	docstring const textfield = qstring_to_ucs4(d->ui.wordED->text());
 	docstring const replacement = qstring_to_ucs4(d->ui.replaceCO->currentText());
-	docstring const datastring = replace2string(replacement, textfield,
-		true, true, true, true);
+	docstring const datastring =
+		replace2string(replacement, textfield,
+			true,   // case sensitive
+			true,   // match word
+			true,   // all words
+			true,   // forward
+			false); // find next
 
 	LYXERR(Debug::GUI, "Replace all (" << replacement << ")");
 	dispatch(FuncRequest(LFUN_WORD_REPLACE, datastring));
diff --git a/src/frontends/qt4/Menus.cpp b/src/frontends/qt4/Menus.cpp
index d0f2e4586d..367f14b120 100644
--- a/src/frontends/qt4/Menus.cpp
+++ b/src/frontends/qt4/Menus.cpp
@@ -783,7 +783,11 @@ void MenuDefinition::expandSpellingSuggestions(BufferView const * bv)
 					MenuItem w(MenuItem::Command, toqstr(suggestion),
 						FuncRequest(LFUN_WORD_REPLACE, 
 							replace2string(suggestion, selection,
-								true, true, false, true, false)));
+								true,     // case sensitive
+								true,     // match word
+								false,    // all words
+								true,     // forward
+								false))); // find next
 					if (i < m)
 						add(w);
 					else
diff --git a/src/lyxfind.cpp b/src/lyxfind.cpp
index 7883475aab..f2c941bcab 100644
--- a/src/lyxfind.cpp
+++ b/src/lyxfind.cpp
@@ -275,9 +275,6 @@ pair<bool, int> replaceOne(BufferView * bv, docstring searchstr,
 	if (forward) {
 		cur.pos() += replacestr.length();
 		LASSERT(cur.pos() <= cur.lastpos(), /* */);
-	} else {
-		cur.pos() -= replacestr.length();
-		LASSERT(cur.pos() >= 0, /* */);
 	}
 	if (findnext)
 		findOne(bv, searchstr, case_sens, whole, forward, false);
diff --git a/status.20x b/status.20x
index b4efefbe5f..8c492b4b45 100644
--- a/status.20x
+++ b/status.20x
@@ -138,6 +138,8 @@ What's new
 - When using a non-default language for the GUI, do not change locale
   settings of child proceses (bug 7741).
 
+- Fix crash in text replacement with spell checker (bug 8238).
+
 
 * DOCUMENTATION AND LOCALIZATION