diff -r 56cd8111b7f7 -r 41300fa6a67c src/gui/text/qtextdocument_p.h
--- a/src/gui/text/qtextdocument_p.h	Tue Jan 26 12:42:25 2010 +0200
+++ b/src/gui/text/qtextdocument_p.h	Tue Feb 02 00:43:10 2010 +0200
@@ -212,6 +212,9 @@
     inline bool isUndoAvailable() const { return undoEnabled && undoState > 0; }
     inline bool isRedoAvailable() const { return undoEnabled && undoState < undoStack.size(); }
 
+    inline int availableUndoSteps() const { return undoEnabled ? undoState : 0; }
+    inline int availableRedoSteps() const { return undoEnabled ? qMax(undoStack.size() - undoState - 1, 0) : 0; }
+
     inline QString buffer() const { return text; }
     QString plainText() const;
     inline int length() const { return fragments.length(); }