New/Edited Calendar Events disappear from Treo after sync

[parisfr]

I'm having a strange problem with Entourage 2004 calendar events
snyching to my Treo 600.

If I create a new event on the Treo or modify an exisiting event, the
next time I sync with Entourage, that event is removed from the Treo.
It still appears in Entourage, but will not show up on the Treo unless
I edit it in Entourage first.

I've tried the "Enable sync for these new devices" option in the
Entourage conduit, but it didn't effect this problem.

Any pointers or help would be appreciated.

Thanks,

Dave