sent message don´t appear on sent itens

[Rodolfo Fontes]

Hi group,

This is my first message on this group, and the first of many...
I work on a company with exchange server and clients using Outlook 2000.
Some users use their notebooks at home on weekends, and write e-mails to be
send on the company, as they arrive.
The trouble is: The message is sent normally, the recipient receives the
message, the confirmation of the message is sent, but the message don´t
appear on sent itens.
All other messages that are sent in company appears without any problem.
Is that any exchange error? or Outlook?

Thanks,
Rodolfo Fontes