I recently installed a NBX V3000 Business Telephone system. The V3000, which serves as the call processor, is located in the main building along with fifteen 3Com NBX telephone sets, a number of computers, network printers, the file server, router, and switch. In a remote building, there are two computers, a network printer, and three 3Com NBX telephone sets. The two buildings are connected via a pair of LinkSys wireless devices - a WAP54G (main building) and the WET54GS5 (remote building) - set for wireless bridge mode.
The computers and the printer in the remote building can communicate with the LAN server and the Internet across the wireless connection to the main building. You can ping the PCs and printer from either side of the wireless link. Unfortunately, the 3Com telephone sets in the remote building cannot connect with the V3000 call processor at the main building. They cannot connect at the MAC level (as in true layer2 LAN bridging) or the IP level. When we manually assign static IP addresses to the phone sets, we cannot ping them at all. However, if you take the same phones and attach them directly to the LAN, they work fine.
I temporarily installed a 3Com Outdoor Wireless LAN bridge between the two buildings. As soon as the connection was established, the phones worked fine.
I have been on LinkSys' technical chat support link four times now but I'm just spinning my wheels with them. One of the documents on the WAP54G does not list the WET54GS5 as a linkable device. I don't know if the documentation says that because the WET54GS5 was not released at the time of printing or if that is an actual proscription. Also, the LinkSys documentation does not go deep enough for adequate troubleshooting.
Router, file server, NBX V3000, PCs, Phone sets, switch ------- WAP54G