http://dovecot.org/releases/1.2/beta/dovecot-1.2.beta4.tar.gz http://dovecot.org/releases/1.2/beta/dovecot-1.2.beta4.tar.gz.sig This release fixes a memory corruption bug related to MODSEQ handling in earlier v1.2 releases. Memory corruption means that it's a security bug and possibly exploitable. MODSEQ code is new in v1.2, so v1.1 and older releases are not affected. Other than that, there is an ESORT bugfix and other fixes that were added to v1.1 branch too.