It depends on how badly you need it. If you can patch it yourself, do that and submit the patch to the author. I'm assuming you have some build or install mechanism you use that installs known versions of your CPAN modules; just make your fixed version the one that gets installed. If you can get along without it, note in your docs that you didn't use it because it's buggy, so the next person along doesn't try to use it. (Mentioning the link to the open bug would be a nice thing to do, in case the bug gets closed.)
Fixing the bug(s) and sending a pull request to the author would be a mitzvah (and a nice way to get into the committers list).