Hi Florian, Thanks for the bug report.
There is a previous bug on this issue [1] [1] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=609241 And one upstream as well [2] [2] http://munin-monitoring.org/ticket/952 This has been fixed in the munin 1.4 branch, and will be included in 1.4.6 (when it's released). Regards, Tom Feiner