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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5)
Gecko/20031007 Firebird/0.7

Description of problem:
Even since I started using RHEL/ES with evolution and sawfish (~2
weeks ago) I have encountered a system hang state where the system is
running but not accessible (does not respond to ANY keyboard input nor
to attempts to access the system remotely, via ssh).  After poking
around and leaving traces of the system available on remote displays,
it would now appear that evolution has a memory leak and after a day
or so it consumes the 512M of physical memory and all the swap space
leaving the system inaccessible.  The last available "top" trace
showed evolution with 63% of the memory.  From this I deduced that
there was a memory leak in evolution.  Subsequent high levels of
paging (with encumbent system slowness) tended to confirm the theory.

In evolution, I use two IMAP accounts, one of them very, very large
(huge numbers of folders containing many thousands of messages). 
Evolution handles this fairly smoothly, with the notable exception of
managing subscriptions.

Version-Release number of selected component (if applicable):
evolution-1.4.5-1

How reproducible:
Always

Steps to Reproduce:
1.Login to an X session configured to run evolution as the mail client
and sawfish 3.0 as the window manager.
2.wait about a day
3.observe system is "frozen" solid.
    

Actual Results:  Had to crash the system (power down) to clear the
condition.

Additional info: