I hit the key sequence for Enlightenment to raise an xemacs window, and poof. Sorry for the shabby backtrace, was compiled with -O3. If I can replicate it with -g I'll follow up. Built from CVS as of yesterday-ish. /Valdis xemacs: X Error of failed request: BadWindow (invalid Window parameter) Major opcode of failed request: 8 (X_MapWindow) Resource id in failed request: 0x380101a Serial number of failed request: 744359 Current serial number in output stream: 744366 xemacs: X Error of failed request: BadWindow (invalid Window parameter) Major opcode of failed request: 12 (X_ConfigureWindow) Resource id in failed request: 0x3801024 Serial number of failed request: 744364 Current serial number in output stream: 744366 xemacs: X Error of failed request: BadWindow (invalid Window parameter) Major opcode of failed request: 2 (X_ChangeWindowAttributes) Resource id in failed request: 0x3801024 Serial number of failed request: 744365 Current serial number in output stream: 744366 ..Lisp backtrace follows: dispatch-event(#<magic-event Expose>) # (unwind-protect ...) # bind (mouse-down xthresh ythresh orig-x orig-y buffer mouse-grabbed-buffer mouse-moved event) mouse-track(#<magic-event Expose>) # bind (command-debug-status) call-interactively(mouse-track) # (condition-case ... . error) # (catch top-level ...) emacs.fatal_error_signal() at 0x1000351c Intrinsic._XtWindowedAncestor(??) at 0xd0d779f8 Geometry.XtConfigureWidget(??, ??, ??, ??, ??, ??) at 0xd0d82530 glyphs-x.x_map_subwindow() at 0x10171904 glyphs.map_subwindow() at 0x10128868 redisplay-output.redisplay_output_subwindow() at 0x100c69c4 redisplay-x.x_output_display_block() at 0x101e9c34 redisplay-output.redisplay_output_display_block() at 0x100c20f0 redisplay-output.output_display_line() at 0x100c35ec gutter.output_gutter() at 0x101efbcc gutter.redraw_exposed_gutter() at 0x101ef21c gutter.redraw_exposed_gutters() at 0x101f1c90 redisplay-x.x_redraw_exposed_area() at 0x101eded0 event-Xt.emacs_Xt_handle_magic_event() at 0x101ca19c event-stream.event_stream_handle_magic_event() at 0x100f95bc event-stream.execute_internal_event() at 0x100f58f0 event-stream.Fdispatch_event() at 0x100faad4 eval.Ffuncall() at 0x1001eee8 bytecode.execute_optimized_program() at 0x101bcd3c bytecode.funcall_compiled_function() at 0x101bed14 eval.Ffuncall() at 0x1001ee5c callint.Fcall_interactively() at 0x100d971c eval.Fcommand_execute() at 0x10020170 event-stream.execute_command_event() at 0x100f2b30 event-stream.Fdispatch_event() at 0x100faefc cmdloop.Fcommand_loop_1() at 0x10215eb4 eval.condition_case_1() at 0x10021fd4 cmdloop.command_loop_3() at 0x10215828 cmdloop.command_loop_2() at 0x102157a4 eval.internal_catch() at 0x100220e4 cmdloop.initial_command_loop() at 0x102160dc emacs.xemacs_21_2_b28_powerpc_ibm_aix4_3_3_0() at 0x100020fc emacs.main() at 0x10000b54