NVRAM Password command broken?

Hi people,

I have noticed a strange issue for about a month, most likely caused by the OS X 10.7.2 update:

When you are using the Open Firmware Password tool you can set the bootup password to prevent the usage of bootup commands like CD booting, PRAM reset, Netboot etc. This works fine.

Since I am depoying company-wide Mac distributions I am using the Terminal command to get this to work, the command is:

nvram security-passwort=<PASSWORD ENCODED>

nvram security-mode=command

Up to now (about a month and a half ago) this worked fine, but now I can see the following issues:

• When setting the passwort or the command I get the correct value from nvram by checking by command (e.g. 'nvram security-mode' correctly give back the command setting).
• If I am setting this on a new Mac it makes no use of it, e.g. I can still access the boot manager without entering the password.
• When I try to remove the option to ask for a password on Macs that are asking for it from previous (working) usage of these commands it goes on to ask for the password. E.g. I tell a "blocked" Mac 'nvram security-mode=', reboot and it still asks me for the password when trying to enter the boot manager.
• When using the Open Firmware Password Tool, e.g. on the Recovery Disk (yes, it is hidden but can be accessed/started by Terminal) it is working alright.

Has anyone an idea what is going on here or has experienced the same issues?

I appreciate any help.

Regards,

Timo