unknown IDE

Hi everybody, I'm trying to work on an old project which was not touched anymore since one year. The guy who did it is not joinable, and the documentation... well... is not the best I've ever seen. :( So here I am: I know that the guy was working on SuSE, and I got a .proj file in the project repertory (I know, it sounds like a cluedo...). I've a little bit searched on the web, but the only repertoried applications creating .proj files are NeXT Interface Builder (Mac) and a molecule simulator - which is absolutely not matching... So, I tried to open it with Kdevelop 3.0.4 and the latest Gambas, but unsuccessfully. Thus, I was wondering if you guys had any idea of which programming environment I could try... Thanx. Cyprien