Simple test which worked for me
test.odp (application/vnd.oasis.opendocument.presentation), 20.82 KB, created by Julien Nabet on 2012-05-21 12:55:30 UTC
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Creator: Julien Nabet
Created: 2012-05-21 12:55:30 UTC
Size: 20.82 KB

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Attachments on bug 47959: 61929