smtp data timeout

[Spokuz]

Hi all

We are having some major problems when sending mails.

Some of our clients just cant send emails. We went to check the log and we ended up with this:

2007-01-08 20:09:37 1H40ah-0004kX-Qi SMTP data timeout (message abandoned) on connection from (nome3979e8150f) [84.90.230.84]
F=<user@email>

The techs at cpanel told us that must be a problem from the connection of the client, but we had the same client had another server in the same datacenter and this never happened. Also, the problem gets solved when we restart exim.

We have mailscanner installed, but the problem also happened when we had it disabled. Is this an exim configuration issue? Should we reset exim to default? I also read of a guy who fixed this by rebooting the server (not shure how but...)

What is the path? Any help will be greatly apreciated