Setup Project - Getting the user selected install directory

Question

I am using Visual Studio 2005. I wrote a Setup Project to install my application. After setup is complete, I need to get the destination folder that the user chose to install to (not the default destination folder, but the one the user actually chose during the install. I found an article that said in Visual Studio 2003, this was done by adding a registry entry (through the Setup project) and setting the value of the entry to [INSTALLDIR]. In Visual Studio 2005, I have no problem adding a registry entry and setting it's value, but [INSTALLDIR] is not recognized as a special tag, and is just treated as a literal string. Has the name of this tag changed in VS 2005? Anyone know how to do this in VS 2005 thanks!