I can not see how it is possible to exchange DATEX II Level C messages using the current exchange WSDLs. The methodology / tool prescribe that Level C model will have a different namespace, which is provided by the modeller of the extension. On the other hand, the two WSDLs are hard-coded to import the DATEX II schema into the Level A/B namespace. I must admit I am not a WSDL expert, but I cannot see how this should work?
It is possible to exchange DATEX II level C. But, not with the two WSDL's those are for level A and B extensions. For level C, you take the two WSDL's change schema to your level C schema (with your own namespace). Then you also should change the target namespace in the WSDL. Then you can exchange level C data.
I see that we might need to document this somewhere. I also have a feeling that we need a guide for extensions in the futur, maybe this can go in there.
I have reset this to "active" to bring the proposal for a documentation hint of the procedure proposed by Jonas to the attention of potential users.
Fixing for Version 2.4 in extension guide.
I think this is supposed to read "Fixing for Version 2.3"