Sounds like some kind of possible corruption.
A decompile may be in order. Try this on the new database container:

http://www.granite.ab.ca/access/decompile.htm

Make sure Name Autocorrect is turned off and double-check your
References as well in the new container.

You may also want to review this good information on corruption:

http://allenbrowne.com.au/ser-47.html

http://www.granite.ab.ca/access/corruptmdbs.htm

http://www.rogersaccesslibrary.com/OtherLibraries.asp#Whittle,Jerry
(See Fix Corrupt Access Database v3.9 Document)

http://www.e-tech.ca/001-AccessFAQ.asp

http://www.everythingaccess.com/tutorials.asp?ID=0

ACC2000: How to Recover Data from a Corrupted Table by Using the DAO Method
http://support.microsoft.com/?id=815280

ACC2000: How to Troubleshoot Corruption in a Microsoft Access Database
http://support.microsoft.com/?id=306204

ACC2000: How to Troubleshoot and Repair a Damaged Jet 4.0 Database
http://support.microsoft.com/?id=209137

ACC2000: How to Recover Data from a Damaged (Corrupted) Table
http://support.microsoft.com/?id=247771

ACC2000: How to Use MS Query to Recover Data from a Damaged Jet 4.0 Database
http://support.microsoft.com/?id=304561

Jetcomp utility available at:
http://support.microsoft.com/?id=273956

Good luck,