the log has this.
MSI (c) (B4:78) [17:12:13:571]: Opening existing patch 'C:\Windows\Installer\2450d0.msp'.
MSI (c) (B4:78) [17:12:13:571]: Opening existing patch 'C:\Windows\Installer\4548bc25.msp'.
MSI (c) (B4:78) [17:12:13:571]: Opening existing patch 'C:\Windows\Installer\30d2dd04.msp'.
MSI (c) (B4:78) [17:12:13:571]: Opening existing patch 'C:\Windows\Installer\9b12058e.msp'.
MSI (c) (B4:78) [17:12:13:586]: Opening existing patch 'C:\Windows\Installer\37a812.msp'.
MSI (c) (B4:78) [17:12:13:586]: Opening existing patch 'C:\Windows\Installer\1787be.msp'.
MSI (c) (B4:78) [17:12:13:586]: Opening existing patch 'C:\Windows\Installer\4db72bbb.msp'.
MSI (c) (B4:78) [17:12:13:586]: Opening existing patch 'C:\Windows\Installer\2ef9d4c5.msp'.
MSI (c) (B4:78) [17:12:13:774]: Original patch ==> C:\Users\aciadmin\Downloads\Exchange2007-KB3056710-x64-EN.msp
It does find these apparently..
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {72C048CD-EEE3-4D28-9140-E41E7773EDA5} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.279.3 Order: 0
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {3CB9909C-1466-4F1A-89C7-72B3BBD61D81} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.279.5 Order: 1
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {E9730840-6730-446B-BBAE-1866F024031E} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.297.2 Order: 2
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {C0DBC2AC-7FA8-46AF-A389-179FAB1D8102} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.298.3 Order: 3
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {9750A7B7-545E-473F-B2BA-5D79157CC280} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.327.1 Order: 4
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {193F22C5-6469-44B9-BBC3-067C725B3FE0} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.342.4 Order: 5
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {373F441B-FE35-42C4-8A6B-84BB431C609D} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.348.2 Order: 6
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {CE370EC7-8AF5-43BE-829C-73CEF5598C5D} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.379.2 Order: 7
MSI (c) (B4:78) [17:12:14:993]: PatchGUID: {BF73925F-9C98-444F-9455-8DC63A79B9C2} ResultantVersion: 8.3.83.6 PatchFamily: E12_DAT Sequence: 8.3.417.1 Order: 8
That looksa like it started with update rollup 8
http://social.technet.microsoft.com/wiki/contents/articles/240.exchange-server-and-update-rollup-build-numbers.aspx#D
This list precisely matches the Windows update history screen.