Hi, I'm trying to compile ruby with the extensions on a Caldera OpenDesktop Linux system, but this keeps happening: make[1]: Leaving directory `/usr/collins/ftp_download/ruby/ruby/ext/digest/sha2' extmk.rb:726: warning: global variable `$install' not initialized extmk.rb:726: warning: global variable `$clean' not initialized extmk.rb:730: warning: global variable `$extinit' not initialized extmk.rb:735: warning: global variable `$extobjs' not initialized gcc -g -O2 -c extinit.c make[1]: Entering directory `/usr/collins/ftp_download/ruby/ruby' gcc -g -O2 -rdynamic main.o ext/extinit.o ext/dbm/dbm.a ext/digest/digest.a ext/etc/etc.a ext/fcntl/fcntl.a ext/gdbm/gdbm.a ext/nkf/nkf.a ext/pty/pty.a ext/readline/readline.a ext/sdbm/sdbm.a ext/socket/socket.a ext/syslog/syslog.a ext/digest/md5/md5.a ext/digest/rmd160/rmd160.a ext/digest/sha1/sha1.a ext/digest/sha2/sha2.a libruby.a -ldl -lcrypt -lm libruby.a -ldb -lc libruby.a -lc libruby.a -lc libruby.a -lc libruby.a -lgdbm -lc libruby.a -lc libruby.a -lc libruby.a -lreadline -lncurses -lc libruby.a -lc libruby.a -lc libruby.a -lc -ltcl -lX11 -lm -ldl -lc libruby.a -lc libruby.a -lc libruby.a -lc libruby.a -lc libruby.a -lc -o ruby /usr/i386-linux/bin/ld: cannot find -lX11 make[1]: *** [ruby] Error 1 Can anyone suggest a work around? Thanks, Martin.