I love that question. I will never get tired of it.

http://puma.bevd.blacksburg.va.us/macbsd/macbsd-docs/faq

  4.1 Why does the installer crash several times with a
  "Trap not implemented error" when I try to use it?

  If you give it a larger memory partition, i.e. increase its preferred memory
  size in its Get Info box,
  it should run just fine. Unfortunately, the program was compiled with a
  memory size that is too small.

I love questions i can answer easily. :)

Francois Pays

>Help! Everytime I try to install the MacBSD 1.1 distribution packages from
>the Installer 1.0, I get an "Unimplemented Trap" error shortly after it
>starts decompressing with my only option being to restart. My system is a
>MacII with 68851 PMMU, True Color (Millions of colors on 13") video
>board, Nat. Semi. Based Ethernet card, 8/80 config, 800k floppy. I'm
>trying to install MacBSD from an APS 540mb external HD onto the 80mb
>internal HD. I'm using APS Disk Tools 2.73 to partition the drives. If
>anybody has experienced and/or can offer some advice or a solution, any
>response to the mailing list or direct email would be greatly appreciated.
>
>-Alfredo Rodriguez
>Carnegie Mellon University