On occasion it has been known for the git hooks to trip up when handling your commits. When they do trip up, they will usually exit out - rejecting the push. Unfortunately, fixing these issues isn't always easy. When the hooks trip up, the actual error which is causing it has usually occurred much earlier in their execution.
While tracing the exact origin of when this error actually happened is usually fairly easy, actually determining how to fix it is much harder. This is especially the case when the bug lies in the information retrieval component, which uses many complex regular expressions to do it's magic.
Please, when reporting bugs with the hooks - provide the commit which is causing the hooks grief. It makes the process of identifying what has broken - and fixing it - much faster.