Auto forwarding.

Hi,
I’ve noticed that loads of spam post a url to pages that autoforward to other pages. I’d like to write myself a little script that checks whether or not a destination page auto forwards, and then marks things as spam.

I know I can load a URL and check whether or not it lists my domain name (since that is already done in Akismet). Is there someway to recognize that the page autoforwaded the visitor?

(BTW, I know this would be time consuming for visitors. I don’t necessarily care if this works in real time, of if the post appears for a few minutes, but gets marked spam a bit later. Just having something check these things every now and then still beats sneaking up onto the blog and sitting there for hours before I wake up in the morning and delete it.)