Dell 1800MP

Tried to search the forums for a like problem with no luck.  My 1800mp will not power off.  When you hit the power button, the menu box explaining to press the power button again to turn the projector off comes up, though when you do press the power button again, the menu blinks off, then right back on.  iF you don't press it again, the menu goes away after 10 or 12 seconds like it was never pushed in the first place.  I've tried pulling out the power cord and holding down the power button for 30 secs and that didn't work.  I've tried to reseat the lamp also.  Didn't work either.

Anybody had this problem before?

Thanks in advance for any help.