ISDN MONITORING

Hello friends,
I have one query about ISDN , i have cisco 7500 router where have severl isdn links configure..i am monitoring this router using OPMANAGER .
Now in general all my isdn links are down i use it as backup whenever framrealy goes down it comes up. i dont want OPMANAGER send me mails whenever it poll all isdn down interfaces...

I want whenever isdn link comes up opmanger send me mail....can anybody guide me how can i configure this trap...using ciscoisdn.mib i can see status of the links. but i dont know how to configure custom monitor that can send me mail whenever and only ISDN link comes up...

Thanks in adv,