How to Establish trusted Domain Between Two Forest over WAN(LL)

i have configured two domain in different forest over Lease line-(HQDC to BODC) in server 2003 R2.i can ping from HO to BO and vice versa.

I want to share the resources between the two forests , But iam unable to establish trusted domain between the two forest.

iam getting an error “unable to contact domain controller”

i’ll be glad if u can post ur suggestion on how to share the resources using Trusted domain.

Thanks in advance

woodybrains