Errors on my production server

I’ve just developed my first 2 rails apps but can’t get them to work on
my server. The support guys are saying something’s wrong with my
application because it generates this error:

./…/config/boot.rb:29: undefined method `gem’ for main:Object
(NoMethodError)
from ./…/config/environment.rb:11
from dispatch.cgi:3

Everything is the same version, I’ve checked that extensively. I’m
running Ruby 1.8.5 and Rails 1.2.3. I developed on Apache and MySQL as
that’s my host’s setup.

One point of confusion for me is that I’ve developed this with
InstantRails 1.6 as my test server which runs Rails 1.2.2, but my
environment.rb says 1.2.3. I ran ‘gem --update-system’, would that
affect it?

It’s pretty urgent that I get this going so if anyone can help me or
point me to a troubleshooting tutorial or whatever I’d be grateful.

sorry, delete this please. i’ll move this to the deployment section.