JSesh is used and supported by the IFAO .
JSesh is featured on sun's swing sightings previews 23!
There is a bug in PDF copy/paste. Apparently, some dimensions are not right (mainly when cartouches are involved). This bug is at least as old as JSesh 5.4. (it doesn't appear in normal PDF export from the file menu).
I'm going to find the source of the problem (I suspect that the correct dimensions are not sent to the clipboard). I take advantage of this occasion to remind users that "strange" behaviour of JSesh can be a bug, and I need to know that there is a bug to correct it :-)
Use normal PDF export if you need PDF. The bug should be fixed in the next version.
Solved in 5.6/5.7