jx makes j look a bit like k from c.
on linux, do the usual 
 $ ./configure
 $ make
and on windows, edit make.bat to set the 
variables required then:
 > make

download jx.tgz

browse the files 
CandK.txt
j.def
j.h
jx.c
jxt.c
Makefile.in
configure
make.bat
run.ijs