Well,i finally did it.
I fixed the sp1 installation on my win 7 ultimate 64bits and got winmail back working,right after..
Here is how.
First:-at march 01-2011, i installed sp1 via automatic updates without any problem,but there was no way to get winmail working again..so i removed sp1 and the troubles began.
After trying to update again (failed 4 times) i had to fix a sqmapi.dll (error C0000135) and after that i got over and over the same error 800B0100 so what did i do.
I found the answer to be rather simple: just by installing and running hotfix
Tool To Repair Windows Updates ( don't forget to restart.!!) and looking after the cbs logfiles which mentioned that everything was fixed/no problems i could install the servicepack.
This time quite a bit larger ,some 235 MB.
Before updating i removed all winmail files from programfiles and replacing it by the original one,which i still had.
After the update i renamed the winmailfolder to winmail-old and i put the before working folder back (i backed it up ofcourse) again in the same programfiles.
Made a shortcut from winmail.exe and attached it on my taskbar.
Yes everything works and i have all my accounts and extra mailfolders back.
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So before the final update (even after 8 times trying) for 64 bits:
1-backup your working winmailfolder
2-replace it by your original one,doesn't have to be 100% virgin..it's not a dealbreaker.
3-fix the install of sp1 by first running the hotfix KB947821.,VERY IMPORTANT..!!!
4-after installing , rename the updated winmail file and copy the original-working-one back into your programfiles
5-your done.
If anyone has more questions i'll be happy to answer them.

Good luck..