Thanks to my colleague, Steve Butcher for this one.
Instead of messing around with the registry, there a utility available that will allow you to make tweaks to the HTC TyTn ( the phone I got ). This was also called the HTC Hermes, among a host of other names by different vendors. As the site article says, the utility itself free, but you need to register and download it and the site is in German only.
If you are either too lazy, or don’t know German, or just can’t be bothered and still want this utility then let me know. Since I have already downloaded this I can send you the cab file directly (its 745 kb).
[I’m rocking out to A Bad Dream by Keane from the album Under the Iron Sea]