I have see the very same issue on my network and seeking a solution to the issue. This "patch has already caused me enough grief with creating Blackberry issues. It seems the Evil Empire has decided on acting as though it is a govenrment agency and "fixxing" things that I did not ask for to be "fixed". This patch did not just affect the DST issue but also inculed several security "fixxes". If MS could have just kept to fixxing the DST issue and leave the security for later maybe they could have gotten it right.
For right now all I can do is have my few users that are being affected is to have them reschedule their meetings. I am a lone admin with 160+ users with 50+ server to take care of so my users are going to have to take care of them selves on this one. The time that they seem to be affected begins on the day of DST change and goes back to normal when the original DST time change was to happen.

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