I did also try the Python 2.5 release tarball and could not reproduce the bug.  Machine info:

bash-3.00$ uname -a
HP-UX td176 B.11.23 U ia64 1928826293 unlimited-user license
bash-3.00$ gcc --version
gcc (GCC) 3.4.3
Copyright (C) 2004 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

bash-3.00$ ./python
Python 2.5 (r25:51908, Jan 31 2007, 15:56:22)
[GCC 3.4.3] on hp-ux11
Type "help", "copyright", "credits" or "license" for more information.
>>>
bash-3.00$