Here is a quick cheat sheet on setting up a 1and1.com Exchange account to use Versa Mail on your Treo 650:

Once you have updated Versa Mail via the latest Treo 650 firmware (V1.20 on unlocked GSM, for example. Check out Palm's support site for the Treo 650 to be sure), create a new account with the following settings:

Account Name: Name of Versa Mail profile (work mail, my mail, company name, etc.)
Mail Service: Exchange Active Sync

User Name: e123456789 (e#########)
Password: password (1and1.com password)

Email Address: you@company.com (this is going to be the reply-to address for your emails
Mail Server: exchange.1and1.com

Advanced Settings -> Incoming Server Settings ->
Port Number: 80
Use Secure Connection (SSL): Don't check this box

Proxy Server: Exchange.1and1.com
Port Number: 80
Proxy authentication ->
Username: e123456789 (e#########)
Password: password (1and1.com password)

I hope this helps everyone!
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