HELP - Fatal error: Cannot instantiate non-existent class

I get this error every time I load my page, from this piece of script.


<?
$xml = new DomDocument('1.0', 'encoding="ISO-8859-1');
$xml->load('http://xoap.weather.com/weather/local/ASXX0016?cc=*&prod=xoap&par=##########&key=################&unit=m&dayf=7');
echo ($xml->weather->loc->dnam);
?>

Can anyone explain why my script isn’t working.
If you want to see the full error you can goto:
http://www.global-insomnia.com/testing/newtest/main.php

Thanks,
THEfish