Description of problem:
SSIA

Version-Release number of selected component (if applicable):
ethereal-0.10.14-1.EL3.1

How reproducible:
Always

Steps to Reproduce:
1. launch ethereal
2. ctrl+k, start capturing
3. helper window with capture statistics (percentage of used protocols, time,
stop button) is opened; close it by the close button on window decoration
created by your window manager, not by the internal Stop button
  
Actual results:
Segfault. Sometimes it's silent crash, sometimes with these details:
Gtk-WARNING **: invalid class type `(unknown)' in cast to `GtkProgressBar'
Gtk-CRITICAL **: file gtkprogressbar.c: line 750 (gtk_progress_bar_update):
assertion `GTK_IS_PROGRESS_BAR (pbar)' failed.
Gtk-WARNING **: invalid unclassed pointer in cast to `GtkLabel'
Gtk-CRITICAL **: file gtklabel.c: line 261 (gtk_label_set_text): assertion
`GTK_IS_LABEL (label)' failed.

Expected results:
capturing is stopped and the main window displays captured data, or possibly
just cancelled capturing, but no crash

Additional info:
Reproduced also on RHEL-2.1. No crash on RHEL-4, just a few GLib-GObject
warnings.