Comment 10 for bug 48128

Myself as well thinks that this is an issue which should be taken care off. I would not mind having an option in evolution to change this (that is not following the local setting).

$ locale
LANG=en_AU.UTF-8
LC_CTYPE="en_AU.UTF-8"
LC_NUMERIC="en_AU.UTF-8"
LC_TIME="en_AU.UTF-8"
LC_COLLATE="en_AU.UTF-8"
LC_MONETARY="en_AU.UTF-8"
LC_MESSAGES="en_AU.UTF-8"
LC_PAPER="en_AU.UTF-8"
LC_NAME="en_AU.UTF-8"
LC_ADDRESS="en_AU.UTF-8"
LC_TELEPHONE="en_AU.UTF-8"
LC_MEASUREMENT="en_AU.UTF-8"
LC_IDENTIFICATION="en_AU.UTF-8"
LC_ALL=

with
~$ export LC_TIME=en_DK.UTF-8 && evolution
I get 24h view but many error messagen in the cli as well

(evolution:26869): gtkhtml-editor-WARNING **: lc: No such language
(evolution:26869): Gtk-WARNING **: GtkSpinButton: setting an adjustment with non-zero page size is deprecated