PayPal not working with Adrevenue ad serving script

[sirket]

I have been using adrevenue for serving ads on my site and I have notices that the Paypal processing doesn't work anymore. It worked in the past but now while processing it goes to paypal's home page. Has any one else encountered this problem? Here is the URL that it is trying to parse when it stops working.

https://www.paypal.com/xclick/business=giftsandcosmetics@yahoo.com&item_name=My%20Article%20Mall+::+My+Article+Mall+-+Advertising&item_number=200&amount=8.99&no_shipping=1&return=http://www.myarticlemall.com/ads/index.php?section=ads&action=thanks&custom=7340672f68ea79b561179bfdbee2a371&cancel_return=http:&f[subid]%20=%20www.myarticlemall.com

Also if you would like to see the error live visit http://www.myarticlemall.com/ads .

Login = test123
Password = test123

Any help would be greatly appreciated.

Thanks,
Sirket