Here we go again with the "dumb upgrade question" of the day...

We have ZFD 3.2 SP3 in our production environment, running on one NW 6.5
server. We are looking at upgrading to the ZEN 6.5 Suite, to include the
desktop, server, handheld, and patch management pieces. In order to do
this, will we need to purchase an additional server(s) to run the "middle
tier" server(s), or is there any way all of these services can run on a
single server?