I was busy last week with meetings in Cupertino, but Adam Donnison wrote me to tell me about the work he did to provide some integration between the two systems. I personally never tried dotProject myself, but for those interested, here is the email from Adam:
It provides the backend for Eventum using Companies and Contacts
within dotProject, and provides a reciprocal view-only listing
of open issues for dotProject users.
It does require the latest CVS version of dotProject (or more
correctly the classes/query.class.php from the latest CVS) to
provide the multi-db query support.
Feedback is very much welcome!