Java UTF-8 support?

[bluegaspode]

Could you please enable UTF-8 support for the Java compiler.
Every second submission I do get's rejected with an error like

./de/bluegaspode/strategy/XYZ.java:212: warning: unmappable character for encoding ASCII
// Versuch #1 - einfach vorw?rts gehen

I just like to write my comments in German which obviously then contains umlauts.
This is easy to fix of course on my side - but it's really cumbersome to rework my comments all the time.