Buffer tabs flickering

I just recently upgraded to b42 (not sure what I was running before, but it was 36+), and I've noticed a problem with the buffer tabs flickering when I move the mouse around in the XEmacs frame (or sometimes apparently just for the heck of it). I toggled display of the tabs, which disabled the flickering for that frame, but started it in one on another workspace. Now after having disabled/enabled the tabs several times, XEmacs is in a state where the tabs will only show up in one frame at a time. Behavior goes kind of like this: F1 == Frame1 F2 == Frame2 Action F1 (ws 1) F2 (ws 2) No tabs Tabs switch-buffer (F1) Tabs Tabs switch-to-ws-2 ?? No tabs switch-to-ws-1 Tabs ?? switch-to-ws-2 ?? No tabs resize-window (F2) ?? No tabs move-modeline (F2) ?? No tabs info (F2) ?? Tabs kill-this-buffer (F2) ?? Tabs switch-to-ws-1 Tabs ?? switch-to-ws-2 ?? No tabs switch-to-ws-1 Tabs ?? switch-to-ws-2 ?? No tabs switch-buffer (F2) ?? Tabs switch-to-ws-1 No tabs ?? switch-to-ws-2 ?? Tabs switch-to-ws-1 No tabs ?? switch-to-ws-2 ?? Tabs My apologies for the verbosity, but it was the best way I could figure to explain it. It seems like only one frame wants to have tabs at a time, and I can get the one that does to switch by doing a switch-buffer (or split-window). I can also get the one that doesn't to temporarily show them anyway by executing some other commands. Through all this, I'm sometimes getting the flickering behavior, and sometimes not. Has anyone else seen anything like this? Is there something I could do to try to help track down the problem?