[Evolution] Expunging

[Svante Signell <srs kth se>]

I assume this question has been asked before, maybe it is even in some
FAQ. I am short of disk space and ~/.evolution is the main cause of
this. Trying to reduce the size of folders I delete a lot of mails, but
the largest folders cannot be expunged due to the lack of disk space. Is
there an option where I can expunge mail folders without a backup copy
is created (or similar happening, remaining disk is reduced before being
increased)?

Please help!