Can I ask exactly which versions of ePO and SQL we're talking about?
EPO verison 4.0 Build 1113
SQL Server 2008 Standard 64-Bit (10.1.2531.0
I thought that might be the case Unfortunately ePO 4 does not support SQL2008 - please see KB 51569 for more details.
My suggestion would be to restore a previous backup to an SQL2005 server, and then upgrade to ePO 4.5 (which does support SQL2008.) You can then move the DB back to the 2008 server as required.