Setting up VM's on there own network

Hi

I have set up a Server and Client (win server 2008 R1 Standard & Win7 Client) in my vsphere.  I want to set the server as a domain controller but dont want this to cause any issues with my current Domain controller for obvious reasons.  The VM's are  on the same network range as the rest of my servers and clients so im thinking if i set up the VM server as a DC then it may somehow cause problems.

Is it possible to change the IP Range of the curent VM's ive set up so there is no way of interfering with the machines on my current IP range