Mojomojo is a CMS being build upon Catalyst by marcus, but I don't know if it's progressed beyond toy status. Frankly, I'd use Trac or Jira. Hacking the code for a tool is ... iffy. It's much cheaper to just pay the developers to add what you want. Think about it - your time is worth between $80-$100/hr. Let's say that it takes you a day to get something up and running. That's about $750 all told. That doesn't count the 3-4 days it took for you to get familiar with the codebase, so add on another $2k. Most CMS owners would gladly take on a little fix for $2k and your company saves $1k and it's now maintained by the owners themselves.

Now, you have what you want, it's blessed by the devs, your company has cred with and exposure to the community, and you've been productive elsewhere. Sounds like a win-win-win all around.