Hello all
Finally I got the "solution".
Not from HP. I got support from an old 3Com Contact that linked me to the H3C developing team.
The WX3000 Controller original labeled as 3Com, not H3C, DOES NOT SUPPORT License extending. This device is for 12 AP and not more.
So we have to exchange the 3Com WX3000 Controller with a H3C WX3000 Controller and HAVE to pay for this. Same FW same CPU.
I need to mention, that we ordered this solution "designed by 3Com". We ordered one Controller, 15 AP and the licensepack for additional 12 Devices!!!
regards
Urs