I will try to field this one, since nobody else is answering:
We use the over-the-air sync which is a part of Zimbra NE with mobility, I am not sure about using local sync software. When we had our Treo 650s phones, I was unable to get contacts to sync, only calendar and email, all over the air.
However when one of my users got a 700p it allowed syncing of contacts calendars and email, so I assume the 755p would be similar. Tasks/notes never were supported as far as I can tell.
However if you are trying to go from Zimbra to Outlook to Palm and back, you may have more difficulty. I haven't tried it, please search the forums and wikis.
Version 6.0.16_GA_2998.NETWORK Apr 4, 2012 MACOSXx86
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