I recently set up psdiff on a few of my servers as a basic means to monitor process activity.
SquirrelMail on Debian/Wheezy (2:1.4.23~svn20120406-2) stopped showing (none) for e-mails that lack a subject. Now I cannot open any subject-less mail because there is nothing to click on.
squirrelmail bug patch
MySQL has many odd quirks. One that bit us recently was this: regression: >=mysql-5.4 utf8 collations are marked as not ascii compatible
performance bug mysql