APEX

I have a web service that I have secured via a OWSM Server Agent. I have added this web service as a reference in my APEX application. I created the reference manually and included all the necessary WS-Security information in the soap:header. The substitution of #APP_USER# for the user is working fine, and I can authenticate the user with no problem. The issue is in the body of the soap:envelope I have another substitution string referencing an item on a page in my application, and the substitution of the value contained within that item never occurs. My web service winds up receiving the string "#P2_TEST_ITEM#" instead of the value of the test item.

I created a second web service that simply takes a string as input, and returns that string as output. I created a reference to this new service in my application, and tried the same substitution string, #P2_TEST_ITEM#. This worked repeatedly. I then secured this service through the OWSM Server Agent, and added the necessary WS-Security items to the soap:header in my reference. When I went back and tried to test the service the substitution repeatedly failed.

Here is the envelope including the WS-Security information I am using for the test service I wrote:

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd">
<soap:Header>
<wsse:Security xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd"
xmlns="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd"
xmlns:env="http://schemas.xmlsoap.org/soap/envelope/" soap:mustUnderstand="1">
<wsse:UsernameToken xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd"
xmlns="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd">
<wsse:Username>test.user</wsse:Username>
<wsse:Password Type="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText">test.password</wsse:Password>
</wsse:UsernameToken>
</wsse:Security>
</soap:Header>
<soap:Body xmlns:ns1="http://xmlns.oracle.com/TestTheParameterService">
<ns1:TestTheParameterServiceProcessRequest>
<ns1:input>input me</ns1:input>
</ns1:TestTheParameterServiceProcessRequest>
</soap:Body>
</soap:Envelope>

I am using APEX v3.0.1.

Has anyone else seen this issue, am I doing something wrong, or is this an already documented bug?