my $response;
eval {
  $response = $soap_handle->call('MyMethod', $security_token, $datagram);
}};

if ($@) {
  print "Error: SOAP call died: $@. \n";
}

##</code><code>##

<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope blah blah blah>
  <soapenv:Header>
    <wsse:Security blah><blah>blah</blah></wsse:Security>
  </soapenv:Header>
  <soapenv:Body>
    <MyMethod xsi:nil="true" />
  </soapenv:Body>
</soapenv:Envelope>

##</code><code>##

  <soapenv:Body>
    <MyMethod/>
  </soapenv:Body>