As you know, there are many languages out there that don't use a SPACE character for word segmentation. For such language, special non-printable characters are used, such ZERO WIDTH NON JOINER or ZERO WIDTH SPACE characters.
It seems XeTeX or XeLaTeX depends on SPACE characters only for the wrapping behavior. Is there a way to change this behavior? Are there packages out there that may help in this? Say, be able to specify characters that Tex can use to determine where to wrap text? If not, I wonder if this is something one can develop?
Any pointers would be much appreciated!