DB2 7.1 on OS/390

I am trying to use OPTHINT by making it use a different index.

So I changed the ACCESSNAME(from X to Y) and MATCHCOL(from 2 to 1) with a HINT.

When I bind with the OPTHINT, it uses the new index Y but MATCHCOL becomes 0. The bind ended with SQLCODE 394 and HINTUSED in PLAN_TABLE says it used the hint.

How can it then apply the HINT partially? I thought either it should apply it completely or reject it with code 395.

Has anyone come across such a thing?

Thanks in advance.