Enable WFQ for atm VC for cisco 7200 router

Okay cisco people I need your help. I simply need to apply a service-policy to a VC on a 7200 router that we have. The map is made (just the class-default fair queuing right now) I just can’t get into VC submode to apply the service policy to the VC. When I try to type pvc VPI/VCI to get into submode I get the following error:
“Cannot configure PVC – already configured using old command method.”
What do I need to do to get in there and apply the service-policy? Thanks.