strtotime() Does not work in IIS 6

I am trying to take an RSS feed, and display it to the page, as part of this, I was testing the strtotime() function like so: <?php $timestamp = strtotime('11 Jan 06 05:25:37 pm GMT -4'); echo $timestamp; echo date('n/j/Y g:i:sa', $timestamp); ?> This returns "-1" however... And then complains about the date being prior to 1970, etc... I was using this same function in an Apache Server, same version of PHP (4.4.1 I believe), in Windows, on this same machine. It was the switch to IIS 6 that made it no longer work... I was using the php4apache2.dll to run the scripts in apache, in IIS I am using php4isapi.dll. Could this be the reason? CGI-BIN was not working at all, giving 500 internal server errors or 400/404 messages depending on how much I played with it. Any insight would be greatly appreciated... Joe