[Dovecot] trash plugin bug?

[Cor Bosman]

Hey all, has anyone ever tried turning on the trash plugin when the directory is already  over quota?  I see some messages being deleted, but it seems it just deletes enough to fit the new email, not enough to go below quota. Example:

. getquotaroot "Spam"
* QUOTAROOT "Spam" "User quota" "Spam Quota"
* QUOTA "User quota" (STORAGE 591036 5242880)
* QUOTA "Spam Quota" (STORAGE 21173 20480)

I now move a 5K message into this folder, and I see:

Apr 23 22:26:43 lmtp1 dovecot: imap(cor): expunge: box=Spam, uid=226337, msgid=<3YVKIIE4II6R0064BA7IM55C2Q4MD01VX12U1I at shedevils.com>, size=12984
Apr 23 22:26:43 lmtp1 dovecot: imap(cor): expunge: box=Spam, uid=226338, msgid=<aab6bffa3ad83767d4a7bc571c31449c at bonus-news.com>, size=5623
Apr 23 22:26:43 lmtp1 dovecot: imap(cor): save: box=Spam, uid=227759, msgid=<20120423191509.F3B584A355B at signal.groundspeak.com>, size=2694

And now:

. getquotaroot "Spam"
* QUOTAROOT "Spam" "User quota" "Spam Quota"
* QUOTA "User quota" (STORAGE 591016 5242880)
* QUOTA "Spam Quota" (STORAGE 21158 20480)
. OK Getquotaroot completed.

This seems like a possible bug.  For one, it shouldnt be allowed to actually save a message into that folder, but it does. The email does end up in the Spam folder even though the folder is over quota. And of course it doesnt clear up enough space to have the new email fit, it just deleted enough to match the 5K. 

Without the trash plugin quota is being properly enforced. 

Everything works fine if you start out below the quota limit btw.

Regards,

Cor

ps: this is 2.1.4, but with the recent trash and quota patches applied.