You would need to clarify what you mean by "port".
If you are just trying to compile some software to run on the PS3, then that is no problem (assuming the code is portable enough to run on PowerPC, and all dependencies are met).
But to actually get it to utilize the PS3's Cell architecture, you are talking about a massive amount of work. You couldn't even call it a port, you would have to basically start from scratch and design the software from the ground up to be aware of the Cell's SPU coprocessors.
The fact of the matter is, when running Linux, the PS3 is just a relatively average PowerPC machine. Linux runs in it's own VM on the PS3, and applications are only aware of the Cell's primary PPC CPU. Sony provides a library that you can use to make Linux applications aware of the SPU's, but you still need to write software around it; it isn't just a matter of linking generic programs to this library and have them suddenly become super-powered.
So in other words, if you can get MLucas compiled and running on the PS3, it is only going to run as fast as a basic single-core machine could run it. You wouldn't be getting anything near the theoretical power of the system, and would be better of putting together a basic dual-core machine for ~$150 than wasting a PS3's time running this software (you could watch a Blu-Ray on it...or something).