subnets and domain

I have the following:
lan1-> router <-T1-> router -> lan2
subnet for lan1 is XXX.XXX.XX1 subnet for lan2 is XXX.XXX.XX2 mask for lan1 255.255.255.0 for lan2 255.255.255.128 PDC & WINS is on LAN1. both are part of same domain. workstations on LAN1 can access shares on LAN1 and LAN2 but workstations on LAN2 can only access shares on LAN1 and not LAN2. Any ideas how I can fix this?