you can try
http://www.gnu.org/software/libc/bugs.html
it will most likely be something they can't replicate for one reason or another
which i guess is why it has not been fixed in the first place.
and they always say file only bugs on current cvs which is the most absurd thing.They are the only people capable of constantly recompling new versions of glibc -- i can't imagine how they do that. plus you already upgraded past the problem as well.
It is, on their side, quite a difficult thing to determine who or what is at fault in this case if they can't reproduce the problem.