ARP table shows MAC address of bridge rather than end node

[archer777]

I have a network in three buildings (A, B & C), one linked with a Linksys WET54G wireless bridge (building C to building B). I can ping any node on the LAN through the wireless bridge, however I can't get out to the Internet through the router in building A, but building A & B route just fine. Checking the ARP table on workstations in building C shows any nodes accessed accross the wireless bridge with the MAC address of the WET54G in building B. I swapped the WET54G for the one on building C and the MAC addresses in the ARP table still shows the WET54G in building B. The router is in building A.
The bridge has been operating fine for about two years, the only change we have just made is to move the router from building B (DSL modem) to building A (new Linksys ethernet router connected to fiber optic Internet provider). The WET54G bridges may have always had this problem but routed OK through the router in building B, but now that it has an extra bridge to cross it doesn't route properly.
Example ARP table:

10.0.0.1 00-11-22-33-44-55 ( IP of router, MAC of WET54G in building B)
10.0.0.2 00-11-22-33-44-55 (IP of server in building B, MAC of WET54G in building B)
10.0.0.3 00-11-22-33-44-55 (IP of any node in building B or A, MAC address of WET54G in building B)

After pinging nodes in building C from building B or A, the ARP table shows the correct MAC addresses for the nodes in building C, so the problem is only from building C accross the bridge to the rest of the LAN.