On a monthly basis, the HMC test team will conduct a Windows update compatibility test (where the major roll-ups and updates will be tested) on different versions of HMC environment.

Windows update compatibility tests (SQL Server 2005 SP3 & Exchange 2007 SP1 RU6was included in this test) on HMC 4.0 as well as HMC 4.5 have completed successfully. This means SQL Server 2005 SP3 & Exchange 2007 SP1 RU6 has been validated for both HM 4.0 and HMC 4.5.

Ref:

SQL Server 2005 SP3 has been validated for HMC 4.0 and HMC 4.5 

Exchange 2007 SP1 RU6 has been validated for HMC 4.0 and HMC 4.5