[Dovecot] fts squat -> webmail, fastcgi timeout: SOLR the answer?

[mailinglists at belfin.ch]

Hi

I turned on fts squat to speed up full text searches over webmail.
This works absolutely fantastic once the mailboxes are indexed.

But when they are indexed for the first time I'm getting a fastcgi timeout
after 30 seconds resulting into a internal server error on the webserver.
In the background the indexing job is getting finished after 80 seconds
for a 25k emails, ~300MB mailbox.

Does solr allow user-offline indexing (no user interaction needed to kick
on indexing) ?
And the other question is, is there any mail user agent that would support
server-side full text indexing and not create own indexes?

Thanks,
Philipp