When installing both modules (soapclient and soap_server) soap server won't generate the WSDL page.
This happens because both modules try to load nuSoap library which causes soap_server to crash on "include_once()"

line 89 in soap_server module:
if (@include_once(realpath(soap_server_nusoap_path()))) {

The include_once() doesn't solve the problem because each module uses his own nuSoap library.