yesterday, after beeing swallowed up by work for months now, I had the time to program a little time & cost tracker.
It is modularized in such a way that you donÂ´t have to touch the source code of your Mantis Instance at all. Just some includes and one SQL command and youÂ´re set. Based an Mantis User-Concept, some users can only view the list while others can enter expenses and admins (or whoever is stated in the conf file) can even remove entries.
Although this is Alpha release stuff you still might like to use it. I will continue to work on it and post here, when it has matured.
Any comments are welcome! Developed in Mantis 0.19.1.