I installed the Service Pack a1 for both Maya and the mental ray satellite. So far, it seems like this has solved the crashing problem (hopefully). I will try to post a log file if Maya does happen to crash again.
Thanks for the help guys.
My specs:
Mac Pro 1,1 - Mac OS X 10.5.8
5 GB DDR2 RAM
2 x 2.67 GHz Dual-Core Intel Xeon
ATI Radeon HD 4870