Hi Florian,
No, I couldn't find out a solution. In my case the only way to do it was create as many Logical Ports as the number of WS that the portal give me to consume. But still this was a static way of solution.
Do it dynamically was imposible to do it, or in my case I didn't find a way.
Sorry for the lack of information information.
If you find out a way, please share it.
I hope you find a solution to the problem.
Thanks a lot.