I (still) have the same problem here. I have a DHD that was locked and branded. I followed HTCDev's procedure to unlock the bootloader and installed a Cyanogenmod ROM (unofficial 10.1) two weeks ago that works great. I've been trying to get my phone unlocked for days with no luck ever since.
I've tried using the HTC unlock tool v. 0.9.5/4 and rooting the phone too. Nothing. Drivers are working fine; program executes as expected, but I still have a locked phone after it finishes. I got an unlock code that I enter after booting and I get a "successful network unlock" message, but the radio seems to remain off. I cannot place calls. Attempting to choose a network operator manually from the settings menu fails; I get a "mobile network unavailable" message when doing so (service providers list does not even appear). I've read threads saying that the only way to get around this is by reverting the phone to its original ROM and HBoot, but I've read elsewhere that workarounds on branded phones shipped with Gingerbread or Froyo (like mine used to run) fail and/or screw up the phone, so I have not tried that. Any ideas or pointers?