Perforce is quite heavy weight, esp for a small team.
I'd strongly consider SVN or GIT, for good solid, well supported VCS, then use the available tooling and best practice (all free from your friendly local internet) to support features you need.
For instance with SVN you can setup "bugtraq" properties that help group changes. We just enter the bug ID with every bugfix commit (you even get a nice input field for it on the check-in GUI forms) and then mutli-commit bugfixes are still grouped.
Reasonable blog post on this feature here : http://markphip.blogspot.com/2007/01/integrating-subversion-with-your-issue.html
Again, it's well supported by the tooling making it a decent call for our team of several.
I've heard better things about GIT recently (heck, the Spring guys are using it and that often speaks volumes) but we are on subversion ourselves, so it's all I can comment on.
