diff --git a/src/frontends/qt2/ChangeLog b/src/frontends/qt2/ChangeLog
index 9331874378..0bd7da7d53 100644
--- a/src/frontends/qt2/ChangeLog
+++ b/src/frontends/qt2/ChangeLog
@@ -1,3 +1,8 @@
+2003-02-07  Juergen Spitzmueller  <j.spitzmueller@gmx.de>
+
+	* QTabular.C (closeGUI): do not change if nothing has to 
+	be changed (bug 849).
+
 2003-01-31  Michael Schmitt  <michael.schmitt@teststep.org>
 
 	* ui/BulletsModuleBase.ui: Replace LaTeX font size names by LyX
diff --git a/src/frontends/qt2/QTabular.C b/src/frontends/qt2/QTabular.C
index 40a71982d0..7e14fdf006 100644
--- a/src/frontends/qt2/QTabular.C
+++ b/src/frontends/qt2/QTabular.C
@@ -328,17 +328,20 @@ void QTabular::closeGUI()
 
 	// apply the fixed width values
 	int cell = inset->getActCell();
-	string str1 = LyXLength(dialog_->widthED->text().toDouble(),
-			dialog_->widthUnit->currentLengthItem()).asString();
+	bool const multicol(controller().isMulticolumnCell());
+	string str1 = widgetsToLength(dialog_->widthED, dialog_->widthUnit);
 	string str2;
+
 	LyXLength llen(tabular->GetColumnPWidth(cell));
-	if (llen.zero())
-		str2 = "";
-	else
-		str2 = llen.asString();
+	LyXLength llenMulti(tabular->GetMColumnPWidth(cell));
+
+	if (multicol && !llenMulti.zero())
+			str2 = llenMulti.asString();
+	else if (!multicol && !llen.zero())
+			str2 = llen.asString();
 
 	if (str1 != str2) {
-		if (controller().isMulticolumnCell())
+		if (multicol)
 			controller().set(LyXTabular::SET_MPWIDTH, str1);
 		else
 			controller().set(LyXTabular::SET_PWIDTH, str1);
@@ -346,13 +349,13 @@ void QTabular::closeGUI()
 
 	// apply the special alignment
 	str1 = fromqstr(dialog_->specialAlignmentED->text());
-	if (controller().isMulticolumnCell())
+	if (multicol)
 		str2 = tabular->GetAlignSpecial(cell, LyXTabular::SET_SPECIAL_MULTI);
 	else
 		str2 = tabular->GetAlignSpecial(cell, LyXTabular::SET_SPECIAL_COLUMN);
 
 	if (str1 != str2) {
-		if (controller().isMulticolumnCell())
+		if (multicol)
 			controller().set(LyXTabular::SET_SPECIAL_MULTI, str1);
 		else
 			controller().set(LyXTabular::SET_SPECIAL_COLUMN, str1);
diff --git a/status.13x b/status.13x
index a795f333a1..b15fa7f869 100644
--- a/status.13x
+++ b/status.13x
@@ -24,10 +24,13 @@ What's new
 
 ** Bug fixes
 
+- fix bug where opening the tabular dialog would mark the document as 
+  changed [bug #849, qt only]
+
 - in the dialogs, replace LaTeX font size names by LyX names for
   consistency reasons and to resolve a translation conflict
 
 - enable the debug level to be set in lyx2lyx
 
-- fix strerror() build problem with some gcc/glibc versions (bug #874)
+- fix strerror() build problem with some gcc/glibc versions [bug #874]