Problem importing PST emails into Exchange 2003 inbox when using ExMerge

I am getting an error when I try to use ExMerge to import emails from a PST file that was created in Outlook 2003 into an Exchange 2003 server store inbox.  The attached ExMerge.log file contains more details on the error.  I found information online explaining that ExMerge has problems when importing from UNICODE formatted PSTs which I guess is what Outlook 2003 produces, but now I don't know how to convert the UNICODE PST into a ANSI PST format.  Are there any free tools that can do the conversion?  Or is there another better way to import PST emails onto the server without having to tell the users to import the emails from the PST themselves?  I have several remote users and they are not technically adept so I want to avoid that route if there is a better way of doing this.  Any help is greatly appreciated