Question: I received the following error:

```
[27-Apr-2009 10:26:06] PHP Fatal error:  Cannot redeclare alphanumeric() (previously declared in /home/iddoc/public_html/lib/common.php:6) in /home/iddoc/public_html/lib/common.php on line 8

```

Notice this:

```
/home/iddoc/public_html/lib/common.php:6) in 
/home/iddoc/public_html/lib/common.php on line 8

```

Here are the offending lines:

```
function alphanumeric($str) {
    return strtolower(preg_replace("/[^A-Za-z0-9]/",'',$str));
}

```

Prior to these lines there are only comments. There is no other declaration of that function anywhere else in that file or any other.

Strange, no?

Answer: 
is this common.php included earlier? That could cause this error.
Check for recursive includes and make sure your blocks are not executed several times.