A gdbinit file is distributed in the python tarball, to ease debugging of python stuff with gdb. See http://wiki.python.org/moin/DebuggingWithGdb for more info. It would be nice to install this file in Gentoo. Thank you !
From you link: (*) If you have gdb 7 it includes the ability to debug Python without the need for python gdb macros. Gentoo has stable gdb-7, so I think this file is unnecessary.
*** This bug has been marked as a duplicate of bug 443510 ***