Can't compile gSOAP with WS-Security support (i.e. wsse-plugin)

On a linux system, I want to create a client app using gSOAP-2.8.8 that interacts with a SOAP service build upon WCF. Therefore, I went through the following:

wsdl2h -t typemap.dat -o myService.h myService.wsdl    
 soapcpp2 -Igsoap/import -CLix myService.h
 

And replaced '#include soapH.h' in wsseapi.h with soapcpp2-generated soapH.h as mentioned in wsseapi.h

Then, the critical step is to manually add the following lines to myService.h

#import "wsse.h"
 
 struct SOAP_ENV__Header"
 {
     mustUnderstand  // must be understood by receiver
     _wsse__Security *wsse__Security;    ///< TODO: Check element type (imported type)
 };
 

...and compile those files like

g++ -DWITH_DOM -DWITH_OPENSSL -Igsoap -Igsoap/import -Igsoap/plugin -o test \
    myService.cpp soapC.cpp soapmyServiceProxy.cpp gsoap/stdsoap2.cpp gsoap/dom.cpp \
    gsoap/custom/duration.c gsoap/plugin/wsseapi.cpp gsoap/plugin/smdevp.c gsoap/plugin/mecevp.c \
    -L/usr/lib -lssl -lcrypt
 

I do get object files for all my sources;-) but still end up with two errors at linking stage.

soapC.cpp:203: undefined reference to `soap_in_ns4__duration(soap*, char const*, long long*, char const*)'
 soapC.cpp:676: undefined reference to `soap_in_ns4__duration(soap*, char const*, long long*, char const*)'
 

Edit: As a workaround I currently substitute soap_in_ns4__duration() with soap_in_xsd__duration(), which is implemented in custom/duration.c

Nevertheless, can anyone give me a hint whats going wrong here?! Thanks in advance

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