I have been getting a lot of email spam lately...and it is making me mad...so now every time i get one, i go to the unsubscribe thing to make sure i am unsubscribed from it.

some of them graciously unsubscribe...thats good...

there are some however, where i get a Mail Delivery Subsystem message back from my ISP saying that the email address to which I sent my unsubscribe message, which was the same email address where the spam told me to email a message to unsubscribe, did not exist....

can they be sued for that? can they be sued for making it impossible to unsubscribe?