Hmmm... I just installed Windows Vista Feature Pack for Wireless (
ITsVISTA KB-Link: KB942567 | ITsVISTA). Apparently, this fix for bluetooth was never made avail for download by Microsoft and only given to OEMs (
Description of the Windows Vista Feature Pack for Wireless).
Since installing, I've rebooted as well as shut down and re-started Desktop Manager and bluetooth is still enabled. Maybe worth a try for those of you having problems with Dell Vista bluetooth and Desktop Manager.
- B.