How do I make a complicated SOAP request from perl?

HI,
I have used SOAP::Lite in the past to make a trivial call from perl, but now I need to send much more information in with the SOAP request, and I can't figure it out.

I'm planning to use Authorize.net to handle subscription transactions for a Web site, and here's an example of the Body of a SOAP call that I would have to make:
<soap:Body>
       <ARBUpdateSubscription xmlns="https://api.authorize.net/soap/v1/">
              <merchantAuthentication>
                     <name>API Login ID here</name>
                     <transactionKey>Transaction Key here</transactionKey>
              </merchantAuthentication>
              <subscriptionId>141414</subscriptionId>
              <subscription>
                     <name>subscription information</name>
                     <paymentSchedule>
                            <interval>
                                   <length>30</length>
                                   <unit>days</unit>
                            </interval>
                            <startDate>2007-12-01</startDate>
                            <totalOccurrences>26</totalOccurrences>
                     </paymentSchedule>
              </subscription>
       </ARBUpdateSubscription>
</soap:Body>
... and that's by far not the most complicated call to SOAP that I would need.
I've looked all over and read manuals, but I can't figure out how to translate this into a form that SOAP::Lite will use.  Is there another technique, or different SOAP module, that I should use for submitting this information, one that wouldn't require that I mangle the format of the information above, or a straightforward way to translate that into SOAP::Lite?
Note that I'm not looking for a SOAP::Lite translation of that exact call described above -- rather I'm looking to learn how to translate calls that complicated into a SOAP::Lite call, or looking for another way to submit that call with the code unchanged.
Thanks for any assistanceStart Free Trial