Fatal error: Possible integer overflow in memory allocation

[eprom]

G'day,

Got a bizzare issue with PHP 5.0.2/Apache constantly generating variations of the following error:

"Fatal error: Possible integer overflow in memory allocation"

At first I traced it through to any line using the $_SERVER[] command and so replaced it with $HTTP_SERVER_VARS[].

This worked fine, however now I seem to get the issue whenever I use a "preg_match" command.

Is there some greater global variable/configuration item that I need to sort out to stop this from happening or is it something else?

For example, trying to implement a VERY basic PHP image gallery script, the following function errors on the "if (preg_match" line - as have several other scripts.

function GetFileList($dirname="."){
global $config;
$list = array();

if ($handle = opendir($dirname)) {
while (false !== ($file = readdir($handle))) {
if (preg_match("/\.(jpeg|gif|png)$/i",$file)) {
$list[] = $file;
}
}
closedir($handle);
}
sort($list);

return $list;
}#-#GetFileList()

Any help would be GREATLY appreciated!

Thanks in advance

Chris