Developing Using Virtual Machines

[Javacat]

I'm guessing that a few people will have had to do this at some point. Basically I'm wanting to develop some software, but to make it and for testing I'm going to make a virtual network. The server will need to be Windows Server 2003 and for the clients I'll need to use XP Pro (and later Linux and Vista machines).

I've been trying to do it on my macbook pro using VMware Fusion, but running just the client and server virtual machines at the same time freezes everything up (I think that it's more to do with the client). I'm also not too keen on the way it handles the network interfaces. I know that the windows version of vmware can do this quite nicely, but I'm wanting to use my mac. If needs be I will go into XP through bootcamp.

So any recommendations for other virtual machine software more suited for building virtual networks? (Parallels, Xen, QEMU ????)
If possible I'd also want to isolate the network they are on from my physical network, but occasionally link it for internet access (or use some sort of proxy).

 

[Squidge]

I just run a single copy of the bog standard VMWare, and then launch multiple virtual machines on a private network (192.168.42.x). They can access the internet by routing packets through 42.1, which is the pc.

I don't bother with the vmware 'server' software.

However, this is on XP, not a MAC...

 

[Vimacs]

I have 5 machines (1 server and 4 workstations) running in a VMware workstation team for testing purposes, runs without a problem here.
Network usually also runs in team mode, but also works well in bridged mode when testing new (real) machines.