Problem with JCO on unicode `

Since we upgraded our SAP R3 instance to unicode, we can no longer connect to it using the JCO. We are using JCO 2.0.5.

The problem occurs after we connected and created a repositoty. Once we perform a getFunctionTemplate on the repository, we get an exception

Thu 13.Sep.2007 16:09:34:0573 CEST Thread-2 com.sap.mw.jco.JCO$Exception: (104)

RFC_ERROR_SYSTEM_FAILURE: ?????????????????RFC_GET_FUNCTION_INTERFACE???????????

The logs directs us to some of the middelware stuff...

Any recommendations ?

Thx,

Dirk