[Evolution] .cache/evolution/mail any cleanup logic?

[Reid Thompson <Reid Thompson ateb com>]

is there any logic in evo with regard to clearing cached items?
I ask because this morning I discovered that I had ~53000 items in

./cache/evolution/mail/1351002422 17754 3 raker2/folders/Inbox


After shutting evo and evo subprocesses down, I tar'd, then rm'd
.cache/evolution/*

$ tar tvf /tmp/evocached.tar  |grep mail/1351002422 17754 3 raker2/folders/Inbox | wc -l
52956

I then restarted evo and allowed it to re-populate.  After finishing I had
~1100 items in 
./cache/evolution/mail/1351002422 17754 3 raker2/folders/Inbox

$ find  mail/1351002422 17754 3 raker2/folders/Inbox |wc -l
11038

thanks,
reid