Does anyone here have experience with Exchange ActiveSync and Act! Link on Treo700p?

I'm trying set up Act! Link to Palm to sync with Act contacts and calendar, but use Exchange ActiveSync to get email from Exchange 2003 server. When I try to sync the treo, I get the following message:

To prevent duplicates caused by an Exchange ActiveSync account and active 3rd party PIM sync conduits, setting the 3rd party conduits to Do Nothing. Please perform another HotSync operation to continue your sync.

I disabled ActiveSync for the user on the server, but the error still comes back.

Anybody knows if this is possible at all? I would think it can be done 'cause not everyone in the world syncs their pda to Outlook.

Thanks in advance,