diff --git a/src/ProgressDialog.py b/src/ProgressDialog.py
index 72dbf3c09..047018e22 100644
--- a/src/ProgressDialog.py
+++ b/src/ProgressDialog.py
@@ -101,11 +101,12 @@ class GtkProgressDialog(gtk.Dialog):
         self.vbox.pack_start(pbar, expand=False, fill=False)
         
         pbar.show()
-        
-        self.resize_children()
-        self._process_events()
+        # this seems to cause an infinite loop:
+        #self.resize_children()
             
         self._progress_bars.append(pbar)
+        # This is a bad idea; could cause deletes while adding:
+        #self._process_events()
         return len(self._progress_bars)-1
     
     def remove(self, pbar_idx):
@@ -114,9 +115,10 @@ class GtkProgressDialog(gtk.Dialog):
         :param pbar_idx: the index as returned from L{add}
         :type pbar_idx: int
         """
-        pbar = self._progress_bars[pbar_idx]
-        self.vbox.remove(pbar)
-        del self._progress_bars[pbar_idx]
+        if pbar_idx is not None:
+            pbar = self._progress_bars[pbar_idx]
+            self.vbox.remove(pbar)
+            del self._progress_bars[pbar_idx]
         
     def step(self, pbar_idx):
         """Click the progress bar over to the next value.  Be paranoid
@@ -158,31 +160,41 @@ if __name__ == '__main__':
     def test(a, b):
         d = ProgressMonitor(GtkProgressDialog)
         
-        s = LongOpStatus("Doing very long operation", 100, 10)
+        s = LongOpStatus("Doing very long operation", 100, 10, can_cancel=True)
     
         d.add_op(s)
         
         for i in xrange(0, 99):
+            if s.should_cancel():
+                break
             time.sleep(0.1)
             if i == 30:
                 t = LongOpStatus("doing a shorter one", 100, 10, 
                                  can_cancel=True)
                 d.add_op(t)
                 for j in xrange(0, 99):
+                    if s.should_cancel(): 
+                        t.cancel()
+                        break
                     if t.should_cancel():
                         break
                     time.sleep(0.1)
                     t.heartbeat()
-                t.end()
+                if not t.was_cancelled():
+                    t.end()
             if i == 60:
                 t = LongOpStatus("doing another shorter one", 100, 10)
                 d.add_op(t)
                 for j in xrange(0, 99):
+                    if s.should_cancel():
+                        t.cancel()
+                        break
                     time.sleep(0.1)
                     t.heartbeat()
                 t.end()
             s.heartbeat()
-        s.end()
+        if not s.was_cancelled():
+            s.end()
     
     w = gtk.Window(gtk.WINDOW_TOPLEVEL)
     w.connect('destroy', gtk.main_quit)
diff --git a/src/gui/utils.py b/src/gui/utils.py
index 3773550a3..654f8b151 100644
--- a/src/gui/utils.py
+++ b/src/gui/utils.py
@@ -88,7 +88,8 @@ class ProgressMeter(object):
     MODE_FRACTION = 0
     MODE_ACTIVITY = 1
     
-    def __init__(self, title, header=''):
+    def __init__(self, title, header='', can_cancel=False, 
+                 cancel_callback=None):
         """
         Specify the title and the current pass header.
         """
@@ -97,9 +98,18 @@ class ProgressMeter(object):
         self.__pbar_max = 100.0
         self.__pbar_index = 0.0
         self.__old_val = -1
+        self.__can_cancel = can_cancel
+        self.__cancelled = False
+        if cancel_callback:
+            self.__cancel_callback = cancel_callback
+        else:
+            self.__cancel_callback = self.handle_cancel
         
         self.__dialog = gtk.Dialog()
-        self.__dialog.connect('delete_event', self.__warn)
+        if self.__can_cancel:
+            self.__dialog.connect('delete_event', self.__cancel_callback)
+        else:
+            self.__dialog.connect('delete_event', self.__warn)
         self.__dialog.set_has_separator(False)
         self.__dialog.set_title(title)
         self.__dialog.set_border_width(12)
@@ -117,11 +127,32 @@ class ProgressMeter(object):
  
         self.__pbar = gtk.ProgressBar()
         self.__dialog.vbox.add(self.__pbar)
+
+        if self.__can_cancel:
+            self.__dialog.set_size_request(350, 170)
+            self.__cancel_button = gtk.Button(stock=gtk.STOCK_CANCEL)
+            self.__cancel_button.connect('clicked', self.__cancel_callback)
+            self.__dialog.vbox.add(self.__cancel_button)
         
         self.__dialog.show_all()
         if header == '':
             self.__lbl.hide()
 
+    def handle_cancel(self, *args, **kwargs):
+        """
+        Default cancel handler (if enabled).
+        """
+        self.__cancel_button.set_sensitive(False)
+        self.__lbl.set_label(_("Cancelling..."))
+        self.__cancelled = True
+
+    def get_cancelled(self):
+        """
+        Returns cancelled setting. True if progress meter has been
+        cancelled.
+        """
+        return self.__cancelled
+
     def set_pass(self, header="", total=100, mode=MODE_FRACTION):
         """
         Reset for another pass. Provide a new header and define number
@@ -132,11 +163,13 @@ class ProgressMeter(object):
         self.__pbar_max = total
         self.__pbar_index = 0.0
         
-        self.__lbl.set_text(header)
-        if header == '':
-            self.__lbl.hide()
-        else:
-            self.__lbl.show()
+        # If it is cancelling, don't overwite that message:
+        if not self.__cancelled:
+            self.__lbl.set_text(header)
+            if header == '':
+                self.__lbl.hide()
+            else:
+                self.__lbl.show()
 
         if self.__mode is ProgressMeter.MODE_FRACTION:
             self.__pbar.set_fraction(0.0)
@@ -171,6 +204,8 @@ class ProgressMeter(object):
         while gtk.events_pending():
             gtk.main_iteration()
 
+        return self.__cancelled
+
     def set_header(self, text):
         self.__lbl.set_text(text)
         while gtk.events_pending():