IR trigger issue

I was trying capture an image of a Kingfisher today, I set the K20d up on tripod, hid myself and prepared to fire remotely when I saw the Kingfisher land.
However I was dissapointed to discover the camera still turns itself off in this mode.
Is there any way to turn this off?

Set-up menu. [Auto Power Off] - select 'Off'

Cheers JohnX, I have spent many an hour in the menu system and missed that one completely