Finally upgraded my iPhone 3G from 3.0.1 to 4.2.1. Installed iBooks (1.2.1) from iTunes, and Sync'ed.

Problem is, I cannot access the iBooks part of the iTunes store. When searching for a book using the store search, the results section for iBooks invites me to download the iBooks app. Already done.

I have removed and deleted iBooks from iTunes and phone, sync'ed and then reinstalled it. I have also restarted all apple related services a couple of times in case of problems there. No change.

Any ideas? 

The iBooks app lists the 3G as a supported platform so I don't think that is the problem.

{No wireless in my current location so I am unable to attempt to get iBooks from the app store using the phone. iTunes only.}