[Evolution] search feature slow - in one account only

[Herr Oswald <herr_oswald gmx de>]

Hello everybody,

I've got 3 accounts in my evo.
One of them holds around 1300 messages. When I do a keyword search, it
takes 23 secs till I get the results.

A second account holds around 1100 messages - the answer comes in
immediately.

Both are the same server, imap etc...

How can I speed up the search at the first account? - Delete cache,
rebuild mailbox, setting?

Thanks a lot in advance,
Wolf