Can't enter accented characters in Monodevelop

I very much like the Monodevelop editor that ships with Unity for Windows, but I can’t enter any foreign characters with it. I’m using the usual ALT-key + ANSI code method, but it doesn’t work. Monodevelop seems to have some shortcut system built-in (Hold down ALT and then a number to jump to a different script window or something?).

This is especially frustrating b/c I can’t enter any special characters in the Unity inspector windows anymore either! ALT just switches modes in the editing window. Has this never worked?

One possible solution would be to edit the file with another text editor (like notepad++).

Another solution for entering regular accented characters would be just to change the Input Method (like explained by Vagaus here) - worked for me.