different charset for viewing and editing in treeview

I'm using a treeview and I change it's charset according to the chosen
language in my program. For example I choose the russian charset. I also
choose a russian keyboard in windows and when I change the text in the
treeview I see russian charaters. But when I press enter the characters
change back to western characters. Entering edit mode again will display the
original russian characters. My question:
How can I modify the treeview so it will always show russian characters?

R. Kruijtzer
Fancom BV