BEx WAD does not work after Java Upgrade to NW 731

Dears,

after the upgrade activity to Netweaver 731 for our BI 70 Ehp1 Abap and  Java EP 70 Ehp1 , we found the BEx WAD is not working anymore .

When we try from the Bex WAD to connect to the BI 731, we recive the msg :

Message Class:     RSBOLAP

Msg n°:                  018

Description:           Java system error: Bean PRTRFC_BASE not found on host xxxxx.xxxx.xxx PROGID=YYYYY.YYY

We checked in the BI Abap system the RFC YYYYY.YYY and the test connection works fine.

Any suggestion ?

Regards