Disapearing underscores

Hello,

I have built arduino gui from svn trunk for ubuntu 10.04. This works fine for the most parts, but there's one problem: in the editor, the underscores disappear whenever the cursor is moved away from the line that contains the underscore. Or to put it another way: the underscores are shown only in the line where the cursor is.

Any ideas what might be causing this problem?

Bug in the editor. Use fontsize 14 or larger.

Thanks, that helped.

Since the underscores are shown as long as the cursor is in the line, I have not even thought it has something tot do with the font size.