I know this post is very old but I found some helpful links to recover Access VBA password
Here is link to brilliant article, this article can help users to recover lost Access VBA password: http://www.trigeminal.com/code/DatabasePassword.bas
Or as darbid said above there are multiple...
Some reasons to split an Access database
1. Multiple users share the data
2. Data is better protected
3. User interface is easy to modify
4. Can use a shared security model
5. Multiple developers can work more effectively
6. Corruption is limited