You have to contact Clickbank and tell them about this. I am not sure, but I think they will reissue a new one for you.
I have the same thing...I have like 7 Clickbank checks sitting at home and at least one of them is over the 90 days. I think I am going to call them.
Great and I have 8 cheques sitting at home !! I went to bank yesterdey and I forgot it was saturday and the bank was close.I will go tomorrow to deposit the other cheques before it get expired also.
Clickbank can definitely re-issue a check.. Just call them or e-mail them about it. I think they charge like 20$ for it (I'm not sure if they charge or don't)