How do I run a load test for a web application that requires an applet to run?

The company I work for has to verify a customer is authorized to access the application. The login page has an applet that calculates the computers unique ID based on different factors such as MAC address, HDD ID, etc... If the users' computer unique ID is not recognized/stored in our database the user is presented the first time login data fields. If the unique ID is recognized the user is displayed the UserID and Password data fields.

I have recorded a login script successfully using the designer tool. The designer script works fine when I replay the script. When I use PushToTest to create a functional test that runs through a browser the PushToTest functional test runs fine. The applet obviously runs for the functional test since the browser opens, runs the applet, displays the correct login fields and successfully executes to completion.

When I use the same successful designer script and try to create a load test that uses sahihtmlunit I get an error. Based on my research the error indicates to me that the UserID field is not available to manipulate. I don't think the security applet runs when I try to run the load test. The application is therefore unable to determine the appropriate login fields to make available.

Is PushToTest even capable of load testing this type application that requires applets?