HarryYou cannot disable/enable 802.11d in our switches.  the information you can find in the SRG is:

The wireless switch supports international roaming per the 802.11d specification.I have attached some FAQs explaining you how 802.11d works.  You have options to enable/disable it in Fusion and/or Mobile companion, depending on the terminal you are using.Also the Fusion 2.55 User Guide has a good explanation for it:

Enable 802.11d

The WLAN adapter attempts to retrieve the country from APs. Profiles which use Infrastructure mode can only connect if the country set is the same as the AP country settings or if the profile country setting is Allow Any Country. All APs must be configured to transmit the country information.

In summary if a MU connects to a WLAN configured in our infrastructure;  and the device has 802.11d enabled, our switch will provide the Country of operation to the MU.If the MU has 802.11d disabled, it will use the Country set up on its wireless profile.Hope this helps

Alex, Thanks for the tip and the FAQ's. The customer is actually only running VoIP on the WLAN. They originally started with Spectralink then went over to the Cisco 7920. All was fine. They have recently tried the 7921's and have had issues. (7920's are EOL) The Systems Integrator (very Cisco centric) tried to push back on the WLAN and was talking about 802.11d etc.  Basically they were trying to pass the buck.  I guess question for all, Has anyone got our WLAN with Cisco 7921's working successfully.  If so, what version of Firmware on the WS5100? Thanks Harry

Harry We had cases in EMEA with customers using the Cisco 7921 phones with our WS5100 running 2.1.3.  they had to enable WME for that to work. I would recommend you to open an case with your TAC to find the root cause. You will need to provide the switche's configuration file, firmware version, network diagram and a wireless trace showing the communication between the phone and the switch.  Make sure you have the lastest software for the Cisco phones and the switch, for the WS5100, version 3.2. If you are using any authentication, make sure it is LEAP or EAP-FAST, which according to Cisco, its the only authentication methods these phones support.