Schema update when exchange 2003 is in the forest

Hi all,<o:p></o:p>

We have a situation where the business have told us to update the AD to 2008 R2 however we have exchange 2003 in this forest.<o:p></o:p>

We appreciate exchange 2003 isn't supported but will the Active directory upgrade fail because of this?<o:p></o:p>

We have a parallel piece of work to remove any relaying the exchange 2003 server is performing but we are a few months away from completing the investigation/changes

thanks in advance

SIAH

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