[MacTUG] mid-2011 imac and firmware password issue and DeployStudio

[Ian Turner]

http://support.apple.com/kb/TS3554

... "Symptoms

Learn what to do if you no longer remember the firmware password that 
you've set or if you see a password dialog when you try to select a 
startup volume on a MacBook Air (Late 2010) and later, MacBook Pro 
(Early 2011), iMac (Mid 2011) and later, and Mac mini (Mid 2011) computer.
Products Affected

MacBook Air (Late 2010), MacBook Pro (17-inch, Early 2011), MacBook Pro 
(15-inch, Early 2011), iMac (21.5-inch, Late 2011), MacBook Pro 
(13-inch, Early 2011), MacBook Air (Mid 2011), iMac (27-inch, Mid 2011), 
iMac (21.5-inch, Mid 2011), Mac mini (Mid 2011)
Resolution

Only Apple retail stores or Apple Authorized Service Providers can 
unlock these computers protected by a firmware password." ...

***************

it appears to be broader than that
We use a step in the workflow in DeployStudio to set our firmware password

That works, once ONLY

If we have to re-image a machine, the workflow hangs at that point, and 
when terminated, of course we get a corrupt, unbootable image

Unfortunately, there is a new (to me) firmware password utility on the 
system disk, which DOESN'T work:
it offers 2 options, one to "not use a password" - that fails. even when 
you DO know the old password

another to change the password, but it will not let you "change it to 
nothing" like the old one used to do


I also tried
http://www.securemac.com/openfirmwarepasswordprotection.php
- booting into Open Firmware - appears to be not possible, once the 
password is set
- pulling memory, and trying to do PRAM reset - appears to be not 
possible, once the password is set

********************

So, does CampusTech, or IST "have the magic tool" so we don't have to 
take, eventually 200+ macs to the Apple store?

Anyone found a reliable way to make anything else work???

Ian