Updating a SilverLight 4.0RC application to 4.0 RTM-Collection of common programming errors

I downloaded the source code to this project:

SilverVNC – a VNC Viewer with Silverlight 4.0 RC

It builds just fine but when I run it I get this message (when the browser launches and presumably from the browser’s SilverLight runtime):

This application was created for an expired beta release of Silverlight. Please contact the owner of this application and have them upgrade their application using an official release of Silverlight.

I have all the requisite SilverLight 4.0 RTM bits installed (I’ve never installed a SilverLight beta or RC on this machine before), what items should I look for in the project to update to get it to run?

I noticed that two of the projects in the solution reference version 3 Silverlight assemblies. I updated these to 4.0 (both the projects and the references to 4.0) but I still get this error. I’ve guessing there’s something in the project file itself that needs tweaking.

Having never written a line of code for SilverLight I’m a bit lost.