If you want to try a different bunch of modules, I'd sugggest XML::Compile. Modifying the http header seems to be covered here. For SOAP::Lite (which I believe SOAP::WSDL uses), modifying the request header is covered here, but I'm not sure how what exactly to specify in SOAP::WSDL.

Update: Basic auth in SOAP::Lite is covered here.

Thanks for the XML::Compile pointer. XML::Pastor also looks promising, at least from the standpoint of my handing it an XSD for generating Perl code for me. As for SOAP::Lite -- I stopped looking at it when it failed to generate an envelope that the server liked. The envelope was sufficiently different from what does work, I set it aside. I think you are right, however, that the authentication problem is probably easier to solve with SOAP::Lite. Perhaps the envelope problem is worth look at in more detail.

# Handcraft XML -- works.

my $SOAP_UI_MIN = <<'END_SOAP_UI_MIN';
<soapenv:Envelope
  xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
  xmlns:ser="http://mysrv.xyz.foo.edu/">
   <soapenv:Body>
      <ser:userSearch>
         <firstName>John</firstName>
         <lastName>Smith</lastName>
      </ser:userSearch>
   </soapenv:Body>
</soapenv:Envelope>
END_SOAP_UI_MIN

# Generated by SOAP::WSDL -- works.

my $PSOAP_WSDL_MIN = <<'END_PSOAP_WSDL_MIN';
<SOAP-ENV:Envelope
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" >
   <SOAP-ENV:Body>
     <userSearch xmlns="http://mysrv.xyz.foo.edu/">
       <firstName xmlns="">John</firstName>
       <lastName xmlns="">Smith</lastName>
     </userSearch>
   </SOAP-ENV:Body>
</SOAP-ENV:Envelope>
END_PSOAP_WSDL_MIN


# Generated by SOAP::Lite -- doesn't work.

my $PSOAP_LITE_MIN = <<'END_PSOAP_LITE_MIN';
<soap:Envelope
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/"
 xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 soap:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
 xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
  <userSearch xmlns="https://mysrv.xyz.foo.edu/idService/userSearchReq
+uest">
    <c-gensym3>
    <firstName xsi:type="xsd:string">John</firstName>
    <lastName xsi:type="xsd:string">Smith</lastName>
    </c-gensym3>
  </userSearch>
  </soap:Body>
</soap:Envelope>
END_PSOAP_LITE_MIN
[download]

The last is rejected with...

Cannot find dispatch method for {https://mysrv.xyz.foo.edu/idService/u
+serSearchRequest}userSearch
[download]

I'm clueless about why SOAP::Lite generates what it does from the WSDL or how to coerce it to generate an acceptable envelope.

The namespaces and other attributes in the SOAP body should be coming from the wsdl, so I can't comment on what's supposed be there.