I'm attaching Xfree86 logs for 2.6.1-bk1-amd64 and Debian sid's 32-bit 2.6.0-k7-smp.
I still get the segfaults with amd64, but I haven't managed an strace. Stupid forking keeps kill my strace! :) -s
XFree86.0.log_2.6.0-1-k7-smp-DEBIAN.bz2
Description: application/bzip
XFree86.0.log_2.6.1-bk1.amd64.bz2
Description: application/bzip
signature.asc
Description: This is a digitally signed message part