9505 Post Office unavailable, with POA 2014 using SOAP SSL


I don't know if there is something strange with my customers system, or I found a bug...

I've just upgraded the Primary and PO server to GW2014, while WebAccess server is still on 2012. Trying to log in gives error 9505 that the PO is unavailable. All communication to https://po-ip:7191/soap is working fine.

Disabling SSL on SOAP and WebAccess is functioning again. As there are no SOAP SSL switches in the webacc.cfg I'm not able to make it work with SSL.

Is there some way to fix this - except upgrading WebAccess to 2014, or disabling SSL on SOAP??