I just installed PT3 and am trying to manually import hands from a Prima file : doesn't work

here is the import status :
2008/02/18 17:29:43: Import beginning
2008/02/18 17:29:43: Import file: E:\Microgaming\Poker\UnibetpokerMPP\GameHistory.dat
2008/02/18 17:29:43: Unrecognized file format.
2008/02/18 17:29:43: Import complete. 0 hands in 1 file were imported. (0 errors, 0 duplicates)
2008/02/18 17:29:43:
2008/02/18 17:29:43: Clustering...
2008/02/18 17:29:47: Clustering complete.
Can you help me ?
thanks
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