That combination may not work as SCVMM 2012 needs OCPM 3.1 but OCPM 3.1 doesn't support SCOM 2007. You will have to upgrade SCOM to 2012. This is all assuming you are Hyper-V role in Windows 2008.
If the VMs are deployed on Windows Server 2012 then you will require SCVMM 2012 SP1 & OCPM 3.2 (not released yet).