Wow! I wrote a routine using libjcsi to draw textboxes using box-drawing unicode characters less than 12 hours ago and I was puzzling over this. Horizontal lines were fine but the vertical ones were broken up. This is wonderful! Thanks! 
I do have a question, though. There seems to be a good chunk of 'unused' space resulting in a moderate-sized gap between WSwingConsoleInterface.xdim and the right edge of the window. There's also a small one between ydim and the bottom of the window. Is there any way to get rid of that? Or is that what the third fix is?
Oh, I have another question: can libjcsi do multi-key input? I want to detect when ctrl + [letter] is pressed, but I can't seem to figure out how.
Hey there,
good to hear that! There are still some problems with small sizes and some fonts - due to hinting, I believe - but it should work for most of them. fontMetrics (which libjcsi uses) isn't entirely accurate. I'm still looking for ways to work around that.
The unused space is directly related to the font problem, since fontMetrics is used to calculate window size. Again, the patch should eliminate most of the unused space, but with some fonts, there might still be problems.
Libjcsi doesn't support multi-key input, but it's not hard to do on your own, using awt. Just have a look around the internet, or make an extra thread for that here in the Dev section.
