Parse errors with functions.php

Everytime I install a hack that involves modifying functions.php I get a parse error on line 1766 (or thereabouts). This has nothing to do with the code I'm putting in, as it's nowhere near line 1766. Help!

[Admin]

You probably have a bracket ( { / } ) missing somewhere... start with a fresh functions.php and rehack it.

[bandersen]

I have installed a hack and get this error message in the PHP Editor:

Parse error: parse error, unexpected $ in A:\member on line 1501

line 1501 is the last line and not near the hack I stalled. What does it mean in general? Thanks.

In the browser it just looks like this:

Parse error: parse error in /forums/upload/member.php on line 1501