Issue with routing and payPal Standard plugin

I have setup payPal standard on my site and the routing seems to be broken or clashing with another plugin in some way.

If I go to pay with PayPal and then cancel on the PayPal site, it is redirected to /Plugins/PaymentPayPalStandard/CancelOrder but I get the error on this page of:

"The API 'PaymentPayPalStandard' doesn't exist"


Any help on tracking this down?

Ignore this, I've tracked down the offending code. Just need to make them play nice now!