This one is probably FAQ.  What Installer are you using?  Probably 1.0, but 
even if it is 1.1, the problem is not enough memory allocated to the 
installer utility.  Try doubling or tripling its memory allocation.  This 
should fix the problem.

BTW, you should probably check out the FAQ, it's located at:

http://www.macbsd.com/macbsd/macbsd-docs/faq/

I hope this helps.

Later.

-- 
Colin Wood                                      ender@is.rice.edu
Consultant                                        Rice University
Information Technology Services                       Houston, TX