SQ02 Illegal Join Condition - MCH1-CUOBJ BM -> AUSP-OBJEK

Goormoring all,

I'm trying to join MCH1-CUOBJ BM with AUSP-OBJEK but I get Illegal Join Condition.

I've noticed that CUOBJ BM is NUMC / lenght 18, OBJEK is CHAR / lenght 50.

Any solutions?

Thanks