Errors with declaring functions

I have a problem with declaring function or better the parser is having problems. I am receiving the following error.

Fatal error: Can't redeclare already declared function in lib.inc.php3 on line 55

I don't have any idea what's wrong..
My functions aren't written twice. So what's up?

I'm a newbie so go light on me if it's a simple answer.

Another question. Is there a troubleshooting guide for php parser errors? Maybe that would be a good project for some bored php programmer.

I found the problem....

and it was easy and stupid and.... what ever.

I'd still like to know if there's a trouble shooting guide or does one have to be a guru to decifer the parser errors.