I am not lucky enough to have HIServer where I work, but I just use the OLE DB drivers that come with IBM's Client Access. I installed the drivers on the intranet server, and from there, I pretty much just connect to the 400 like any other datasource. And it's dsnless. I don't have the connection string that I use since I'm at home, but I believe there's a DB2 one at
www.connectionstrings.com.
Ray at home