In eog (Eye of Gnome) 2.30.2, I found no way to specify size unit in mm in
Page Setup dialogs:
So I have to convert these sizes in inches to sizes in mm.
I'm using CUPS as the print backend. Should I configure CUPS to switch to use mm as the default size unit?
The same problem occurred in Google Chrome 17.0 and many other applications, when I want to custom paper sizes in the system print dialog: