Email client software

Hi, I need some suggestion(s) for an email client. One of my client has 50 users & is using 'Jana Server' as email server. Currently all the computers are in 5 different workgroups and all the users are using 'Outlook Express' as email client. Now he wants to move to domain with roaming profiles so that users can access their data from any machine. Now the problem is that OE does not support network drives. Can anyone suggest any good email client alternative which can store its data on network drives? I have tried Eudera, but users are facing lot of difficulties in it.

 

Steve, going up to Exchange/Outlook is a very costly alternative with a lots of handholding and administration required for Exchange server. Looking for a cheaper/better alternative. I am happy with Janaserver, only need info on email client.