Page Revisions Do Not Show

Good afternoon,

I've downloaded and installed PmWiki 0.5.3 on SuSE 8.2.
diff (GNU diffutils) 2.8.1

Everything seems fine except that page revisions do not show up.
I get the restore link but the actual lines and changes do not show.

Is there a variable I need to set or some configuration re: diff.

This seems like a super-nice wiki and I'm excited about using it in my dept.

Thanks in advance,

Steve Fox
UT CMHC