Not getting IP address when Access Control is ticked.

Hi there, I hope someone can assist me with getting up a SSID with my MSM760.

I have many SSIDs which are all for seperate VLANs.

When i set these up to just authenticate on WPA2, i get an IP on the right subnet and everything works - We have a proxy which have 3 DHCP servers on that gives the relevant leases.  However when i tick the Access Control so i can authenticate with 802.1x, it authenticates fine but i get no IP address.  I have looked everywhere and can't seem to find why this is happening.

If you need any more information about the VLANs please let me know.

Thanks.