About the only way to do that with the JET engine is to have some alpha characters in that field in the first few records. I agree, this is a major issue.
I don't know if the new ACE drivers are any better - have you tried them out yet? The ACE drivers are available here. If you try them out, please get back with us on how they work out!
Wayne
Microsoft Certified Master: SQL Server 2008
Author - SQL Server T-SQL Recipes