We have installed a 526 Wireless controller and 520 express switch. As far as we can tell all is configured ok. We use wpa/enterprise with Radius server an clients authenticate OK and get an IP lease from our windows (SBS) dhcp server. Unfortunately we cannot ping this server, but we can ping all other computers on the network. The reason seems to be that we get a rogue mac address for the server's IP. If we wireshark it we see the server initially replying to the ARP WHO HAS correctly followed by another from a ASKYCOM device. This MAC then appears in the 520 gigabit uplink's mac table.
If we look on the network to which the 520 is connected this MAC address does not appear, so it seems as if it is being generated within the wireless system!
Anyone have any ideas?