You can use a conditional field to trap it
{IF {Mergefield MDP} <> "12:00:00 AM" "{Mergefield MDP}" }
should do the trick.

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Graham Mayor - Word MVP
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> Empty date field in XL when mailmerged reads:
>
[quoted text clipped - 4 lines]
> Any Ideas? I was wondering whether i can use an 'If' command with
> this, or maybe some formatting option?