Are you trying to connect to the WLC using a wireless client? In that case you need to have the manage via wireless option enabled. By default it is disabled. You can enable this feature in the Management page of the WLC GUI.
Management > Mgmt via Wireless > Enable Controller Management to be accessible from Wireless Clients.
I've seen something like this, too, on the WiSM when I had to enable telnet (ick) to run the LWAPP upgrade utility. It would not answer telnet on the maintenance port addresses (it even was nice enough to say so with a message) until after I had successfully telnetted to the corresponding management address. After that, it worked and I was able to run the upgrade utility. Same thing happened twice with two separate machines using the same address (at different times), so it's probably ARP related. Very strange. Don't know what to make of it.