[c-nsp] OSPF Default Gateway Route Question

[DEMON]

I have a question regarding OSPF that I was hoping I could get some help with. Here's my scenario:

I have 7200VXR's uBR that i´m using as access router ( to connect clients with cable modems). This router, connect to 2 diferent gateways ( 2 juniper M20) by a passport switch  I use static routes for this scenario, but if one of the gateway fails, the cisco router don´t change de ip route "gateway" and continue to send traffic for it. How can i configure 2 default gateway in cisco uBR by ospf?  It´s possible ? 
Does anyone have some examples of doing this? Are there other
alternatives to doing what I've suggested above?

Thanks,
DEMON