Hey Brad
I've never used the NCHAR and NVARCHAR stuff, so maybe that is the way to go, but I understood that you might run into trouble having your database character set as WE8ISO8859P1. It might be worth running a quick test with a new UTF8 database, just to rule that out.
I presume you tried the AOLServer config file settings described above?
Does it work if you hardcode some Chinese characters directly into an INSERT statement in a Tcl proc?
Brian