Why am I getting this error...

[Dark_Wizard]

It's only on some sites and it's driving me nuts...

The error is:
Parse error: parse error, expecting `']'' in /home/heroclan/public_html/forums/vchallenge.php(172) : eval()'d code on line 303


and here is the offending line in the template:
<option value="12:00" $wartimeselected[12:00]>12:00</option>

and the PHP code:

PHP Code:

if(isset($HTTP_POST_VARS["wartime"])) $wartimeselected[$HTTP_POST_VARS["wartime"]]="selected"; 


It doesn't like this [12:00] anyone know why?