diff --git a/FL/Fl_Text_Buffer.H b/FL/Fl_Text_Buffer.H
index 92f4792ff..45771c99e 100644
--- a/FL/Fl_Text_Buffer.H
+++ b/FL/Fl_Text_Buffer.H
@@ -1,5 +1,5 @@
 //
-// "$Id: Fl_Text_Buffer.H,v 1.3.2.5 2002/09/20 19:59:45 easysw Exp $"
+// "$Id: Fl_Text_Buffer.H,v 1.3.2.6 2002/11/05 19:53:50 matthiaswm Exp $"
 //
 // Header file for Fl_Text_Buffer class.
 //
@@ -83,6 +83,7 @@ class FL_EXPORT Fl_Text_Buffer {
     void remove(int start, int end);
     void replace(int start, int end, const char *text);
     void copy(Fl_Text_Buffer* fromBuf, int fromStart, int fromEnd, int toPos);
+    int undo(int *cp=0);
     int insertfile(const char *file, int pos, int buflen = 128*1024);
     int appendfile(const char *file, int buflen = 128*1024)
       { return insertfile(file, length(), buflen); }
@@ -249,5 +250,5 @@ class FL_EXPORT Fl_Text_Buffer {
 #endif
 
 //
-// End of "$Id: Fl_Text_Buffer.H,v 1.3.2.5 2002/09/20 19:59:45 easysw Exp $".
+// End of "$Id: Fl_Text_Buffer.H,v 1.3.2.6 2002/11/05 19:53:50 matthiaswm Exp $".
 //
diff --git a/FL/Fl_Text_Editor.H b/FL/Fl_Text_Editor.H
index d436e73c8..f146d61f5 100644
--- a/FL/Fl_Text_Editor.H
+++ b/FL/Fl_Text_Editor.H
@@ -1,5 +1,5 @@
 //
-// "$Id: Fl_Text_Editor.H,v 1.1.2.5 2002/11/05 06:45:40 matthiaswm Exp $"
+// "$Id: Fl_Text_Editor.H,v 1.1.2.6 2002/11/05 19:53:50 matthiaswm Exp $"
 //
 // Header file for Fl_Text_Editor class.
 //
@@ -88,6 +88,7 @@ class FL_EXPORT Fl_Text_Editor : public Fl_Text_Display {
     static int kf_cut(int c, Fl_Text_Editor* e);
     static int kf_paste(int c, Fl_Text_Editor* e);
     static int kf_select_all(int c, Fl_Text_Editor* e);
+    static int kf_undo(int c, Fl_Text_Editor* e);
 
   protected:
     int handle_key();
@@ -102,6 +103,6 @@ class FL_EXPORT Fl_Text_Editor : public Fl_Text_Display {
 #endif
 
 //
-// End of "$Id: Fl_Text_Editor.H,v 1.1.2.5 2002/11/05 06:45:40 matthiaswm Exp $".
+// End of "$Id: Fl_Text_Editor.H,v 1.1.2.6 2002/11/05 19:53:50 matthiaswm Exp $".
 //
 
diff --git a/src/Fl_Text_Buffer.cxx b/src/Fl_Text_Buffer.cxx
index 50cf59723..eb8c3b235 100644
--- a/src/Fl_Text_Buffer.cxx
+++ b/src/Fl_Text_Buffer.cxx
@@ -1,5 +1,5 @@
 //
-// "$Id: Fl_Text_Buffer.cxx,v 1.9.2.12 2002/09/20 19:59:45 easysw Exp $"
+// "$Id: Fl_Text_Buffer.cxx,v 1.9.2.13 2002/11/05 19:53:50 matthiaswm Exp $"
 //
 // Copyright 2001-2002 by Bill Spitzak and others.
 // Original code Copyright Mark Edel.  Permission to distribute under
@@ -69,6 +69,26 @@ static const char *ControlCodeTable[ 32 ] = {
   "dle", "dc1", "dc2", "dc3", "dc4", "nak", "syn", "etb",
   "can", "em", "sub", "esc", "fs", "gs", "rs", "us"};
 
+static char* undobuffer;
+static int undobufferlength;
+static Fl_Text_Buffer* undowidget;
+static int undoat;	// points after insertion
+static int undocut;	// number of characters deleted there
+static int undoinsert;	// number of characters inserted
+static int undoyankcut;	// length of valid contents of buffer, even if undocut=0
+
+static void undobuffersize(int n) {
+  if (n > undobufferlength) {
+    if (undobuffer) {
+      do {undobufferlength *= 2;} while (undobufferlength < n);
+      undobuffer = (char*)realloc(undobuffer, undobufferlength);
+    } else {
+      undobufferlength = n+9;
+      undobuffer = (char*)malloc(undobufferlength);
+    }
+  }
+}
+
 /*
 ** Create an empty text buffer of a pre-determined size (use this to
 ** avoid unnecessary re-allocation if you know exactly how much the buffer
@@ -249,6 +269,7 @@ void Fl_Text_Buffer::replace( int start, int end, const char *s ) {
   call_predelete_callbacks( start, end-start );
   deletedText = text_range( start, end );
   remove_( start, end );
+  //undoyankcut = undocut;
   nInserted = insert_( start, s );
   mCursorPosHint = start + nInserted;
   call_modify_callbacks( start, end - start, nInserted, 0, deletedText );
@@ -311,6 +332,45 @@ void Fl_Text_Buffer::copy( Fl_Text_Buffer *fromBuf, int fromStart,
   update_selections( toPos, 0, copiedLength );
 }
 
+/*
+** remove text according to the undo variables or insert text 
+** from the undo buffer
+*/
+int Fl_Text_Buffer::undo(int *cursorPos) {
+  if (undowidget != this || !undocut && !undoinsert) return 0;
+
+  int ilen = undocut;
+  int xlen = undoinsert;
+  int b = undoat-xlen;
+
+  if (xlen && undoyankcut && !ilen) {
+    ilen = undoyankcut;
+  }
+
+  if (xlen && ilen) {
+    undobuffersize(ilen+1);
+    undobuffer[ilen] = 0;
+    char *tmp = strdup(undobuffer);
+    int at = undoat;
+    replace(b, undoat, tmp);
+    if (cursorPos) *cursorPos = mCursorPosHint;
+    free(tmp);
+  }
+  else if (xlen) {
+    remove(b, undoat);
+    if (cursorPos) *cursorPos = mCursorPosHint;
+  }
+  else if (ilen) {
+    undobuffersize(ilen+1);
+    undobuffer[ilen] = 0;
+    insert(undoat, undobuffer);
+    if (cursorPos) *cursorPos = mCursorPosHint;
+    undoyankcut = 0;
+  }
+
+  return 1;
+}
+
 /*
 ** Insert "text" columnwise into buffer starting at displayed character
 ** position "column" on the line beginning at "startPos".  Opens a rectangular
@@ -1279,6 +1339,17 @@ int Fl_Text_Buffer::insert_( int pos, const char *s ) {
   mLength += insertedLength;
   update_selections( pos, 0, insertedLength );
 
+  if ( undowidget==this && undoat==pos && undoinsert ) {
+    undoinsert += insertedLength;
+  }
+  else {
+    undoinsert = insertedLength;
+    undoyankcut = (undoat==pos) ? undocut : 0 ;
+  }
+  undoat = pos+insertedLength;
+  undocut = 0;
+  undowidget = this;
+
   return insertedLength;
 }
 
@@ -1289,10 +1360,34 @@ int Fl_Text_Buffer::insert_( int pos, const char *s ) {
 */
 void Fl_Text_Buffer::remove_( int start, int end ) {
   /* if the gap is not contiguous to the area to remove, move it there */
-  if ( start > mGapStart )
+
+  if ( undowidget==this && undoat==end && undocut ) {
+    undobuffersize( undocut+end-start+1 );
+    memmove( undobuffer+end-start, undobuffer, undocut );
+    undocut += end-start;
+  } 
+  else {
+    undocut = end-start;
+    undobuffersize(undocut);
+  }
+  undoat = start;
+  undoinsert = 0;
+  undoyankcut = 0;
+  undowidget = this;
+
+  if ( start > mGapStart ) {
+    memcpy( undobuffer, mBuf+(mGapEnd-mGapStart)+start, end-start );
     move_gap( start );
-  else if ( end < mGapStart )
+  }
+  else if ( end < mGapStart ) {
+    memcpy( undobuffer, mBuf+start, end-start );
     move_gap( end );
+  }
+  else {
+    int prelen = mGapStart - start;
+    memcpy( undobuffer, mBuf+start, prelen );
+    memcpy( undobuffer+prelen, mBuf+mGapEnd, end-start-prelen);
+  }
 
   /* expand the gap to encompass the deleted characters */
   mGapEnd += end - mGapStart;
@@ -1843,8 +1938,10 @@ void Fl_Text_Buffer::remove_selection_( Fl_Text_Selection *sel ) {
     return;
   if ( isRect )
     remove_rectangular( start, end, rectStart, rectEnd );
-  else
+  else {
     remove( start, end );
+    //undoyankcut = undocut;
+  }
 }
 
 void Fl_Text_Buffer::replace_selection_( Fl_Text_Selection *sel, const char *s ) {
@@ -2397,5 +2494,5 @@ Fl_Text_Buffer::outputfile(const char *file, int start, int end, int buflen) {
 
 
 //
-// End of "$Id: Fl_Text_Buffer.cxx,v 1.9.2.12 2002/09/20 19:59:45 easysw Exp $".
+// End of "$Id: Fl_Text_Buffer.cxx,v 1.9.2.13 2002/11/05 19:53:50 matthiaswm Exp $".
 //
diff --git a/src/Fl_Text_Editor.cxx b/src/Fl_Text_Editor.cxx
index 4d44e8529..eda8a0adb 100644
--- a/src/Fl_Text_Editor.cxx
+++ b/src/Fl_Text_Editor.cxx
@@ -1,5 +1,5 @@
 //
-// "$Id: Fl_Text_Editor.cxx,v 1.9.2.11 2002/11/05 06:45:40 matthiaswm Exp $"
+// "$Id: Fl_Text_Editor.cxx,v 1.9.2.12 2002/11/05 19:53:50 matthiaswm Exp $"
 //
 // Copyright 2001-2002 by Bill Spitzak and others.
 // Original code Copyright Mark Edel.  Permission to distribute under
@@ -93,8 +93,8 @@ static struct {
   { FL_Page_Up,   FL_CTRL|FL_SHIFT,         Fl_Text_Editor::kf_c_s_move   },
   { FL_Page_Down, FL_CTRL|FL_SHIFT,         Fl_Text_Editor::kf_c_s_move   },
 //{ FL_Clear,	  0,                        Fl_Text_Editor::delete_to_eol },
-//{ 'z',          FL_CTRL,                  Fl_Text_Editor::undo	  },
-//{ '/',          FL_CTRL,                  Fl_Text_Editor::undo	  },
+  { 'z',          FL_CTRL,                  Fl_Text_Editor::kf_undo	  },
+  { '/',          FL_CTRL,                  Fl_Text_Editor::kf_undo	  },
   { 'x',          FL_CTRL,                  Fl_Text_Editor::kf_cut        },
   { FL_Delete,    FL_SHIFT,                 Fl_Text_Editor::kf_cut        },
   { 'c',          FL_CTRL,                  Fl_Text_Editor::kf_copy       },
@@ -105,6 +105,7 @@ static struct {
 
 #ifdef __APPLE__
   // Define CMD+key accelerators...
+  { 'z',          FL_COMMAND,               Fl_Text_Editor::kf_undo       },
   { 'x',          FL_COMMAND,               Fl_Text_Editor::kf_cut        },
   { 'c',          FL_COMMAND,               Fl_Text_Editor::kf_copy       },
   { 'v',          FL_COMMAND,               Fl_Text_Editor::kf_paste      },
@@ -386,6 +387,16 @@ int Fl_Text_Editor::kf_select_all(int, Fl_Text_Editor* e) {
   return 1;
 }
 
+int Fl_Text_Editor::kf_undo(int , Fl_Text_Editor* e) {
+  e->buffer()->unselect();
+  int crsr;
+  int ret = e->buffer()->undo(&crsr);
+  e->insert_position(crsr);
+  e->show_insert_position();
+  if (e->when()&FL_WHEN_CHANGED) e->do_callback(); else e->set_changed();
+  return ret;
+}
+
 int Fl_Text_Editor::handle_key() {
 
   // Call fltk's rules to try to turn this into a printing character.
@@ -466,5 +477,5 @@ int Fl_Text_Editor::handle(int event) {
 }
 
 //
-// End of "$Id: Fl_Text_Editor.cxx,v 1.9.2.11 2002/11/05 06:45:40 matthiaswm Exp $".
+// End of "$Id: Fl_Text_Editor.cxx,v 1.9.2.12 2002/11/05 19:53:50 matthiaswm Exp $".
 //