I'm having a similar issue.
In SEPM (Version: 12.1.2015.2015), the Mac 10.6.8 client I just updated to RU2 using the installer I created from SEPM shows the client version as 12.1.0001.8888.
On the client 10.6.8 MacBook, when I get info on the SEP client app, it shows 12.1.2015 (2015)
//Edit: I also have the same experience on a 10.8.2 iMac....