...and it was a good idea. Haven't seen a spontaneous reboot in quite a while.
Tried the postal2mp demo again after the boot and no blowup, but now I'm getting-
Copyright 2003 Running With Scissors, Inc.
Copyright 2001 Epic Games, Inc.
GL_EXT_bgra not supported - bailing out.
Exiting due to error
And sure enough, glxinfo32 is missing a big chunk of OpenGL extensions.
Ahhhh- switching back to the 4496 x86-32bit libs brings back the extensions. Weird, must be too big a mismatch between 5328 and 4499. Try, try again.