Connection to server, but Offline working?

User has a notebook and is working with hislocal mail database, but he has still a vpn

connection to the lan.

If he gets per replicator a memo as a reply, and

he open it, the client is connecting to the server and the user has to wait, until the memo

opens.

But if he gets a new memo, then it opens asap.

Why does the client connect to the server, if the memo is a reply ?

Thnx lot.