My Book Studio for Mac not unlocked at boot

I have my WDC My Book Studio 2TB which is connected through a firewire 800 cable to an iMac running Lion 10.7.1.

The drive it’s encrypted using its built-in capabilities, without WD Smartware installed on a Mac; to unlock the drive I manually run WD unlock from VCD.

The issue: if I have the drive connected during the boot the VCD doesn’t come up and I have
to manually disconnect the drive and reconnect it.

Does anybody else experiencing something like this?

Regards

That sounds like your Mac is not giving enough power to awaken the drive, do you have the same problem on USB?