Thanks for your help. Here's the output:
> patch -p2 <frank_patchset_11964.diff
missing header for unified diff at line 9 of patch
can't find file to patch at input line 9
Perhaps you used the wrong -p or --strip option?
The text leading up to this was:
--------------------------
|Index: install.php
|===================================================================
|RCS file: /forum21/install.php,v
|retrieving revision 1.176
|retrieving revision 1.177
|diff -u -a -r1.176 -r1.177
|--- install.php 11 Jul 2009 11:15:56 -0000 1.176
|+++ install.php 13 Jul 2009 17:20:17 -0000 1.177
--------------------------
File to patch: install.php
patching file install.php
Hunk #1 FAILED at 621.
patch unexpectedly ends in middle of line
Hunk #2 FAILED at 783.
2 out of 2 hunks FAILED -- saving rejects to file install.php.rej