Oct 03, 2011 04:12 PM|joshj|LINK
You can use a schema.ini file to specify columns and their data types. If you don't have them declared, the driver will try to auto-detect data types. The schema.ini file needs to be in the same folder as the import file.
MSDN reference: http://msdn.microsoft.com/en-us/library/ms709353.aspx