With the Release of SCCM Configmgr 2012 SP1 RTM,When you deploy Secondary Site from its Parent site ,it will install SQL Server Express 2008 R2 Service Pack 1 (SP1) but as you can see from below snap (SQL server Requirements),the minimum required cumulative update is CU6 which you will have to install it manually.
Read more on http://support.microsoft.com/kb/2688247/en-us?sd=rss&spid=1060:SQL
