gtk error messages

"J. E. Peters" <[email protected]> Fri, 30 Jan 2004 21:59:37 +0100
Newsgroups gmane.comp.mozilla.devel.gtk
Organization T-Online
Message-ID <[email protected]>
Hello news group,

running Mozilla 1.6 I encountered the following error 
message:Gtk-WARNING **: invalid cast from `GtkSuperWin' to `GtkWidget'
This messages shows up in the xterm from which I start mozilla.  It is 
independent wether I use the binary version or my self-compiled mozilla.

Has anybody seen the same error message on his system?

regards,
J. E. Peters