You can not create a database connection directly to an AS400 database in 10.1. You can only connect to supported database versions which in the case of DB2 would be through the DB2 9.7 client. The DB2 9.7 client can not connect to an AS400 either unless you purchase DB2 Connect from IBM. In our case, we are publishing AS400 data through a FLEX app and a server version of DB2 Connect would be required to the tune of $2K - $3K. An expenditure that we are not budgeted for.
So, just to recap ...
ESRI eliminates the ability to use OLE/DB connections so if you want to connect to DB2 on an AS400, then you must use the DB2 9.7 client. However, this client can�??t access the AS400 unless you buy DB2 Connect for $2K +. Nice, huh?
Does ESRI understand how many of their clients maintain legacy systems in the AS400 environment and the impact that their unfortunate decision is having on them? What are we to do when accessing the plethora of other data sources via ODBC. Does ESRI appreciate the flexibility inherent in being able to access external data sources using a long accepted connection method in OLE/DB/ODBC?
The workaround that I devised above is unworkable for accessing data live due to poor performance. I am presently developing data replication scripts with the hope that ESRI will realize that generic OLE/DB connectivity should never have been taken away and should be restored ASAP.