This is a basic HTTP encoding and formatting question. I need to log in from a RESTFixture to a PHP web service. I need to pass in the account, username, and password, as POST variables just as a login page does. Wireshark shows that my login page formats it as accountNumber=accounttest&username=usertest&password=passtest When I do that in the test, I get a POST array of $_POST: Array ( [accountNumber] => accounttest [amp;username] => usertest [amp;password] => passtest ) That would work but the "amp;" obviously makes it so that PHP doesn't find the username. Content type is the same for both live and the test. [CONTENT_TYPE] = application/x-www-form-urlencoded Here are a few other formats I've tried with results. In all three cases, it fails to parse so all fields end up in one array entry. input: accountNumber=accounttest%amp;username=usertest%amp;password=passtest Result: $_POST: Array ( [accountNumber] = accounttest%amp;username=usertest%amp;password=passtest ) input: accountNumber=accounttest;username=usertest;password=passtest Result: $_POST: Array ( [accountNumber] => accounttest;username=usertest;password=passtest ) input: accountNumber=accounttest%26username=usertest%26password=passtest Result: $_POST: Array ( [accountNumber] = accounttest&username=usertest&password=passtest ) So the last one correctly converts the %26 to &, but doesn't break the items apart into array elements.