Unfortunately you decided that you didn't want Outlook as your email client, but that you did want a Windows Mobile phone. That's kinda like saying I want to sync my ipod with my Windows Media Player.
It states very clearly on the Activesync download page (
http://www.microsoft.com/windowsmobile/en-us/downloads/microsoft/activesync-download.mspx) :
"You must use Microsoft Outlook 2002, Outlook 2003, or Office Outlook 2007 to sync your e-mail, contacts, tasks, and notes from your computer."
As far as I can see, there is accepted standard for synchronizing with anything else.
You can try BirdieSync, it appears the be the best alternative out there. I'm still skeptical of how well it would work.
http://www.birdiesync.com/