Breaking change in MDAC ADODB COM components in Windows 7 Service Pack 1 (repost with MSDN liveID)

Question

As my MSDN subscription is connected to this liveID, I repost my question in the hope to get a faster answer:
After I installed Service Pack 1 on my Windows 7 x64 Ultimate my applications which use MDAC 2.8 COM components for database access do not work on other Windows versions any more.
I hunted this down to changed Interface IDs in the msadoxx.tlb files. On Windows 2008 R2 e.g. the IID of dispinterface _Connection is {00000550-0000-0010-8000-00AA006D2EA4} (defined in msdado28.tlb). When I lookup the same dispinterface on my Windows 7 with
SP1 (RTM from MSDN) I see this IID {00001550-0000-0010-8000-00AA006D2EA4}.
That means that all code produced on Windows 7 SP1 using ADODB cannot be run on any other version of Windows as the IIDs differ.
The CLSIDs still match, so the COM objects get created but due to different IIDs they cannot be used.
I really hope I am missing something as this change seems to be a massively breaking change in the MDAC API.
To verify the error you can use code like this in VB6 or equivalent in VB.Net or C# and compile it on Win7 SP1 and run it on Win7 RTM or older versions of Windows:
Dim cn As ADODB.Connection
Dim o As Object
Set o = CreateObject("ADODB.Connection") ' this does still work
Set cn = o ' this errors when compiled on Win 7 SP1 and run on older versions of Windows due to the changed IID of the dispinterface _Connection
Regards,
SvenC

Answer 1

Ok NEW Fix:
===================================================================
---- / start: getting around Trusted Installer / ----
STEP 1) Change owner of  
"%CommonProgramFiles(x86)%\system\ado\msado28.tlb" to administrator or whatever your current local user is... 
Then close all security windows.
You might have to change this registry setting in order to change the owner:  
(although I'm not sure, I did though.)
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\TypeLib\{2A75196C-D9EB-4129-B803-931327F72D5C}
Right click, Permissions, Advanced, Owner, Change owner to Administrators, Click OK, OK
STEP 2) Back in the file properties, under Security, Change Permissions to Full Control for your new owner.
---- / end: getting around Trusted Installer / ----
STEP 3) 
Unregister it:
Run C:\Windows\Microsoft.NET\Framework\v4.0.30319\regtlibv12 -u "CommonProgramFiles(x86)%\system\ado\msado28.tlb"
STEP 4) Copy in legacy msado28.tlb file (get this from a non SP1 Windows 7 Machine), i.e. overwrite the last one.
STEP 5) Re-register the new one:
Run C:\Windows\Microsoft.NET\Framework\v4.0.30319\regtlibv12 "CommonProgramFiles(x86)%\system\ado\msado28.tlb"
** Now VB6 compiles from a Windows 7 SPK1 machine that reference MDAC 2.8 should work now automatically without changing anything in the project file or references
Is there somewhere I can download the legacy msado28.tlb file since I have the only W7 machine in the organization?