This problem could be due to an incomplete arp entry.
This issue is documented in Cisco bug ID CSCsa90418.
Choose one of these workarounds for this issue:
This issue is first found in version 12.3(4)JA. It is first fixed in version 12.3(7)JA. To statically configure arp, refer to arp (global). To download the latest Cisco IOS version, refer to the Download Center.For more information, refer User Guide for the CiscoWorks Wireless LAN Solution Engine, 2.9. For more related information on WDS, refer to Wireless Domain Services Configuration.
Client / Device cannot authenticate
CiscoWorks Wireless LAN Solution Engine (WLSE)
Point to multi point network
Unauthenticated and Unassociated
Wireless Domain Services (WDS)