Remove 1 vCPU from VM with 2 vCPUs

Hi,

We have some server with Windows 2008r2 Datacenter and Vmware Esxi 5.1.

We have a lot of server with 2 vCPUs, we need to remove 1 vCPU from these servers and add these vCPU to other servers.

There is a problem?  (perfomance, kernel, etc)

Thanks.