I have been meaning to mention how cool and informative the info is in the WSE3 trace files. Not only does it show you the soap, but leaves a step by step trail of processing. Here is a sample file from a simple HelloWorld request being made from a client using a UsernameoverX09 policy asserstion.

<?xml version="1.0" encoding="utf-8"?>
<log>
  <outputMessage utc="9/23/2005 7:04:53 PM">
    <processingStep description="Unprocessed message">
      <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
        <soap:Body>
          <HelloWorld xmlns="http://tempuri.org/" />
        </soap:Body>
      </soap:Envelope>
    </processingStep>
    <processingStep description="Entering soap filter Microsoft.Web.Services3.Design.UsernameOverCertificateAssertion+ClientOutputFilter" />
    <processingStep description="Exited soap filter Microsoft.Web.Services3.Design.UsernameOverCertificateAssertion+ClientOutputFilter" />
    <processingStep description="Processed message">
      <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:wsa="http://schemas.xmlsoap.org/ws/2004/08/addressing" xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd">
        <soap:Header>
          <wsa:Action wsu:Id="Id-3055d475-5038-45ae-9909-d7feb1241b7b">http://tempuri.org/HelloWorld</wsa:Action>
          <wsa:MessageID wsu:Id="Id-bc312d98-8815-4c65-a015-2cf87409140c">uuid:80c57c6f-7226-49a6-95ba-51c160841d30</wsa:MessageID>
          <wsa:ReplyTo wsu:Id="Id-d3c52946-1153-4ef6-85df-4e80506bb0a2">
            <wsa:Address>http://schemas.xmlsoap.org/ws/2004/08/addressing/role/anonymous</wsa:Address>
          </wsa:ReplyTo>
          <wsa:To wsu:Id="Id-047058e6-d0e9-4592-8d10-2df4cd13d976">http://localhost:1624/WSE3_Demo2_Service/Service.asmx</wsa:To>
          <wsse:Security soap:mustUnderstand="1">
            <wsu:Timestamp wsu:Id="Timestamp-71acb0d5-9d5c-4d6d-beba-585045011528">
              <wsu:Created>2005-09-23T19:04:53Z</wsu:Created>
              <wsu:Expires>2005-09-23T19:09:53Z</wsu:Expires>
            </wsu:Timestamp>
            <xenc:EncryptedKey Id="SecurityToken-2eb49508-1d19-4dc8-ac98-df6037e4dce3" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
              <xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-1_5" />
              <KeyInfo xmlns="http://www.w3.org/2000/09/xmldsig#">
                <wsse:SecurityTokenReference>
                  <wsse:KeyIdentifier ValueType="http://docs.oasis-open.org/wss/2004/xx/oasis-2004xx-wss-x509-token-profile-1.1#X509ThumbprintSHA1" EncodingType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-soap-message-security-1.0#Base64Binary">h9ksyrcUww2w4LrmubC2W11t988=</wsse:KeyIdentifier>
                </wsse:SecurityTokenReference>
              </KeyInfo>
              <xenc:CipherData>
                <xenc:CipherValue>(this goes on for a while...) Udj=</xenc:CipherValue>
              </xenc:CipherData>
            </xenc:EncryptedKey>
            <wssc:DerivedKeyToken wsu:Id="SecurityToken-a4ae21b8-bdab-4011-a7b2-c5e8f65bae44" Algorithm="http://schemas.xmlsoap.org/ws/2005/02/sc/dk/p_sha1" xmlns:wssc="http://schemas.xmlsoap.org/ws/2005/02/sc">
              <wsse:SecurityTokenReference>
                <wsse:Reference URI="#SecurityToken-2eb49508-1d19-4dc8-ac98-df6037e4dce3" ValueType="http://docs.oasis-open.org/wss/2005/xx/oasis-2005xx-wss-soap-message-security-1.1#EncryptedKey" />
              </wsse:SecurityTokenReference>
              <wssc:Generation>0</wssc:Generation>
              <wssc:Length>16</wssc:Length>
              <wssc:Label>WS-SecureConversationWS-SecureConversation</wssc:Label>
              <wssc:Nonce>0waVpgMtJcwLe6nu2EJfWA==</wssc:Nonce>
            </wssc:DerivedKeyToken>
            <xenc:ReferenceList xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
              <xenc:DataReference URI="#EncryptedData-95a05b43-87ff-4265-8220-0b0301998d5c" />
            </xenc:ReferenceList>
            <xenc:ReferenceList xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
              <xenc:DataReference URI="#EncryptedData-474cdefc-1a57-4848-9d3b-195021ac5f88" />
            </xenc:ReferenceList>
            <xenc:EncryptedData Id="EncryptedData-474cdefc-1a57-4848-9d3b-195021ac5f88" Type="http://www.w3.org/2001/04/xmlenc#Element" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
              <xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#aes128-cbc" />
              <KeyInfo xmlns="http://www.w3.org/2000/09/xmldsig#">
                <wsse:SecurityTokenReference>
                  <wsse:Reference URI="#SecurityToken-a4ae21b8-bdab-4011-a7b2-c5e8f65bae44" ValueType="http://schemas.xmlsoap.org/ws/2005/02/sc/dk" />
                </wsse:SecurityTokenReference>
              </KeyInfo>
              <xenc:CipherData>
                <xenc:CipherValue> (this goes on for a while...) =</xenc:CipherValue>
              </xenc:CipherData>
            </xenc:EncryptedData>
            <wssc:DerivedKeyToken wsu:Id="SecurityToken-ef9f2efd-b777-4288-9a93-f7b24b9eb083" Algorithm="http://schemas.xmlsoap.org/ws/2005/02/sc/dk/p_sha1" xmlns:wssc="http://schemas.xmlsoap.org/ws/2005/02/sc">
              <wsse:SecurityTokenReference>
                <wsse:Reference URI="#SecurityToken-2eb49508-1d19-4dc8-ac98-df6037e4dce3" ValueType="http://docs.oasis-open.org/wss/2005/xx/oasis-2005xx-wss-soap-message-security-1.1#EncryptedKey" />
              </wsse:SecurityTokenReference>
              <wssc:Generation>0</wssc:Generation>
              <wssc:Length>16</wssc:Length>
              <wssc:Label>WS-SecureConversationWS-SecureConversation</wssc:Label>
              <wssc:Nonce>+G94xbAd/DYLEKwIvHIdTA==</wssc:Nonce>
            </wssc:DerivedKeyToken>
            <Signature xmlns="http://www.w3.org/2000/09/xmldsig#">
              <SignedInfo>
                <ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" />
                <SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#hmac-sha1" />
                <Reference URI="#SecurityToken-6d4fff15-de0b-449d-ab5e-47ac5f5b4592">
                  <Transforms>
                    <Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
                  </Transforms>
                  <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
                  <DigestValue>XOXZQd6B320w7VI/HbimntQgLI0=</DigestValue>
                </Reference>
                <Reference URI="#Id-3055d475-5038-45ae-9909-d7feb1241b7b">
                  <Transforms>
                    <Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
                  </Transforms>
                  <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
                  <DigestValue>1kE5FH5eNF4vkBKNE9o0/vCJvks=</DigestValue>
                </Reference>
                <Reference URI="#Id-bc312d98-8815-4c65-a015-2cf87409140c">
                  <Transforms>
                    <Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
                  </Transforms>
                  <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
                  <DigestValue>t/FJbUnIn0gLqoLt6eMRTFOTI/Q=</DigestValue>
                </Reference>
                <Reference URI="#Id-d3c52946-1153-4ef6-85df-4e80506bb0a2">
                  <Transforms>
                    <Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
                  </Transforms>
                  <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
                  <DigestValue>9QxbDw3l7++M8PbJMur9JxcPf4c=</DigestValue>
                </Reference>
                <Reference URI="#Id-047058e6-d0e9-4592-8d10-2df4cd13d976">
                  <Transforms>
                    <Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
                  </Transforms>
                  <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
                  <DigestValue>9l1Au73puBn71S7N/1XIBe2vRSY=</DigestValue>
                </Reference>
                <Reference URI="#Timestamp-71acb0d5-9d5c-4d6d-beba-585045011528">
                  <Transforms>
                    <Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
                  </Transforms>
                  <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
                  <DigestValue>Ys2mZfoq7z+Ix/XyIYWTIDUvm28=</DigestValue>
                </Reference>
                <Reference URI="#Id-8d5987f2-3dd0-41aa-8dc5-5551bc171011">
                  <Transforms>
                    <Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
                  </Transforms>
                  <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
                  <DigestValue>PkZhQS+mXa/s8BC0x09fp7BOeB8=</DigestValue>
                </Reference>
              </SignedInfo>
              <SignatureValue>tJZfFrgNccXPYc91i41uHxdrzXk=</SignatureValue>
              <KeyInfo>
                <wsse:SecurityTokenReference>
                  <wsse:Reference URI="#SecurityToken-ef9f2efd-b777-4288-9a93-f7b24b9eb083" ValueType="http://schemas.xmlsoap.org/ws/2005/02/sc/dk" />
                </wsse:SecurityTokenReference>
              </KeyInfo>
            </Signature>
          </wsse:Security>
        </soap:Header>
        <soap:Body wsu:Id="Id-8d5987f2-3dd0-41aa-8dc5-5551bc171011">
          <xenc:EncryptedData Id="EncryptedData-95a05b43-87ff-4265-8220-0b0301998d5c" Type="http://www.w3.org/2001/04/xmlenc#Content" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
            <xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#aes128-cbc" />
            <KeyInfo xmlns="http://www.w3.org/2000/09/xmldsig#">
              <wsse:SecurityTokenReference>
                <wsse:Reference URI="#SecurityToken-a4ae21b8-bdab-4011-a7b2-c5e8f65bae44" ValueType="http://schemas.xmlsoap.org/ws/2005/02/sc/dk" />
              </wsse:SecurityTokenReference>
            </KeyInfo>
            <xenc:CipherData>
              <xenc:CipherValue>(this goes on for a while...) ==</xenc:CipherValue>
            </xenc:CipherData>
          </xenc:EncryptedData>
        </soap:Body>
      </soap:Envelope>
    </processingStep>
  </outputMessage>
</log>