emerge tclx error

[zrl]

rm -f tclx.tcl
cp /var/tmp/portage/tclx-8.3-r1/work/tclx8.3/tcl/runtime/tclx.tcl tclx.tcl
rm -f buildidx.tcl
cp /var/tmp/portage/tclx-8.3-r1/work/tclx8.3/tcl/runtime/buildidx.tcl buildidx.tcl
/var/tmp/portage/tclx-8.3-r1/work/tclx8.3/unix/runtcl /var/tmp/portage/tclx-8.3-r1/work/tclx8.3/unix/tools/genindex.tcl tcl.tlib
Error: can't read "env(TCL_LIBRARY)": no such variable
while executing
"lappend dirs $env(TCL_LIBRARY)"
(procedure "tclInit" line 11)
invoked from within
"tclInit"
while
initializing application (Tcl_AppInit?)
make[1]: *** [tcl.tndx] Error 255
make[1]: Leaving directory `/var/tmp/portage/tclx-8.3-r1/work/tclx8.3/tcl/unix'
make: *** [TCLX] Error 2

!!! ERROR: dev-tcltk/tclx-8.3-r1 failed.
!!! Function src_compile, Line 66, Exitcode 2
!!! (no error message)