Upgrade Exchange 5.5 to Exchange 2003

I am currently trying to upgrade our email system. We have a Windows 2003 server running our Active directory, and a Windows 2000 server running Exchange 5.5. When I run ForestPrep, I get an error that says; “Setup failed while installing sub-component Microsoft Exchange Organization-Level Container Object with error code 0x1037AE6 (please consult the installation logs for a detailed description). I can’t find the logfile that the exchange setup has been created. My question is: Can MS Exchange 5.5 Be upgraded to Exchange 2003? Is there anyone out there that has successfully done it? I need help please.