couldn't connect to display "plow.activestate.com:30"
    while executing
"load /opt/ActiveTcl-8.4/lib/tk8.4/../libtk8.4.sl Tk"
    ("package ifneeded" script)
    invoked from within
"package require Tk"
    (file "test-for-tk.tcl" line 1)

Your Tcl installation (tclsh) fails to find Tk package.
One of possible reasons is missing file 'pkgIndex.tcl' in ..../tk8.4/
directory; Please check if you can feed 'package require Tk' to tclsh