If you want to use Ruby/Tk (tk.rb and so on), you must have
tcltklib.so which is working collectry. If you fail to call 
'require "tcltklib"', you may not have tcltklib.so. 
Even if there is a tcltklib.so on your Ruby library directry, 
it will not work without Tcl/Tk libraries (e.g. libtcl8.4.so) 
on your environment. You must also check that your Tcl/Tk is 
installed properly. 

--------------------------------------------
 ( the following is written in EUC-JP )

Ruby/Tk (tk.rb �ʤ�) ��Ȥ��������ˤϡ�tcltklib.so ��������
ư���Ƥ��ʤ���Фʤ�ޤ��󡥤⤷ require "tcltklib" �˼��Ԥ���
�褦�ʤ顤tcltklib.so ��¸�ߤ��Ƥ��ʤ��Τ��⤷��ޤ���
���Ȥ� Ruby �Υ饤�֥��ǥ��쥯�ȥ�� tcltklib.so ��¸�ߤ���
�����Ȥ��Ƥ⡤�¹ԴĶ��� Tcl/Tk �饤�֥�� (libtcl8.4.so �ʤ�) 
���ʤ���е�ǽ���ޤ���Tcl/Tk �����������󥹥ȡ��뤵��Ƥ��뤫
�ɤ���������å����Ƥ���������

==========================================================
                Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)