Checking for application existance

[GrahamS]

Is there a nice easy way to check if an application (one that has inbuild VBP support) is installed on a particular machine?

I have two machines running VBP, one of which doesn't have support for MSDEV. I would like to set up a build rule to skip building the MSDEV builds so that I can use the same script on both machines. (I currently check against COMPUTERNAME but that means the machine name is hard wired - which is so tacky)