Bug in nnimap?

["Sven Bretfeld" <sven.bretfeld@gmx.ch>]

Hi to all

I'm using Gnus as an imap client since two years now. What annoys me
ever since, is that Gnus keeps record of old mail headers of long
deleted emails (not expired, deleted!).

When entering a Group with C-u, Gnus asks if I want to see the several
thousands of messages in that group. In reality there are only about one
or two hundred mails within that imap folder. But Gnus actually displays the
headers of every email that had ever lived in that group -- no matter if
it's long deleted or shifted to another imap-folder. The Summary buffer
displays the headers with the "O" mark, turning to "G" when one selects
the message.

This is annoying, especially if you have to worry about space
limitations on the server. Gnus is not capable to tell how many mails
actually exist in the respective folder.

Is that a bug in nnimap? Is it a feature? Can somebody tell me how to
prevent Gnus from keeping track of old headers or how to refresh its
memory? 

Can anybody even reproduce that behavior?

Thanks

Sven