About three days ago, I noticed the exim mailqueue started filling up on one of my servers, and upon inspecting some of the emails using # exim -Mvb $ID, I noticed they were being sent to some system email address (which is not a real address), and the body of the messages were as follows:

(process:8259): Pango-WARNING **: Invalid UTF-8 string passed to pango_layout_set_text()

I'm wondering what could be causing this strange issue, as I've never heard of 'pango' at all... I've never seen that function used in my lifetime!

It seems the process id (PID) is for an apache process, though, as the pids are always gone by the time I use # ps -aux to look them up.

Edit: Whoops! Forgot to include the subject - looks like it's actually munin-cron that's bringing up the issue:

Subject: Cron  /usr/bin/munin-cron --force-root