Having an issue with an E00007 error during a customer checkout using the CIM system.

Up to the point that the error occurs, here is what has happened:

1.  Account is in Test mode

2. Code has been altered to use Test account data

3. Customer has come to the site and has successfully been issued a customerProfileID using the test system

4. Customer has successfullly added a credit card to the CIM system.

5. Customer places order,  and the system then fires up the request back to AuthNet to get that customers payment option details

Then I get this:

ErrorE00007User authentication failed due to invalid authentication values.

Here is the code I am using to make the getCustomerProfileRequest :

<?xml version="1.0" encoding="utf-8"?>
<getCustomerProfileRequest xmlns="AnetApi/xml/v1/schema/AnetApiSchema.xsd">
<merchantAuthentication>
<name>123456789</name>
<transactionKey>ABCDEFGHIJKLMNOP</transactionKey>
</merchantAuthentication>
<customerProfileId>9876543</customerProfileId>
</getCustomerProfileRequest>

Since the system is working as it is supposed to up until this point,  and I don't think that this particular request method uses anything different to make the connection than other methods on the system that are working - I can't figure this one out.

Just to be sure,  here are the actual connection variables in the vars.php file I'm using:

$g_apihost = "apitest.authorize.net";
$g_apipath = "/xml/v1/request.api";

Any ideas why this is happening?  I'm open to suggestions :)

Thanks,

WHeis