In previous versions of Symantec Endpoint Protection and Symantec AntiVirus, the virus definitions were shared between the virus protection client and other Symantec products that used virus definitions. In Symantec Endpoint Protection 12.1, this is no longer true. Other Symantec products that use virus definitions must be configured to update separately from Endpoint Protection.
For instructions on how to configure your Symantec product with Symantec Endpoint Protection 12.1, read the document appropriate to your product:
So, your 'SEPM 12' means the SEP 12.1? If so, then the SEP 11 clients work well with it.
Will SEP 11 clients work with SEPM 12?
I ask because I am planning to update to version 12, once it is no longer marked as beta. However, if SEPM 12 does not work well with SEP 11 clients, I might have to think about it a little more.