Steven,

I've never used an AS400 as a backend. Is the error you are getting is that when one person is running a SPT that the other user can't even get a connection? or that their SPT command fails?

have you looked at the aerror() data when you can't connect or a SPT fails?

Is the database potentially put into Single User mode where only one connection to it can exist?

>The exclusive connection string is my guess, but I don't know how to designate either shared or exclusive with SPT.