[ns] problem installing ns-allinone-2.1b8a

[tigerbell <yingjie@cis.ohio-state.edu>]

Dear all:
I got the following errors in  Build ns-2.1b8a:
============================================================
* Build ns-2.1b8a
============================================================
creating cache ./config.cache
Restarting: ./configure --disable-static --enable-gcc --enable-debug
--enable-develop --with-tcl=/nfs/ruby/haldar/conser/tcl8.3.2.linux/ --w
ith-tcl-ver=8.3 --with-tk=/nfs/ruby/haldar/conser/tk8.3.2.linux
--with-tk-ver=8.3 --with-otcl=/nfs/ruby/haldar/conser/otcl
--with-tclcl=/nfs
/ruby/haldar/conser/tclcl  --without-defaultoptions
loading cache ./config.cache
checking host system type... i686-pc-linux-gnu
checking target system type... i686-pc-linux-gnu
checking build system type... i686-pc-linux-gnu
checking for gcc... gcc
checking whether the C compiler (gcc  ) works... yes
checking whether the C compiler (gcc  ) is a cross-compiler... no
checking whether we are using GNU C... yes
checking whether gcc accepts -g... yes
checking for c++... c++
checking whether the C++ compiler (c++  ) works... yes
checking whether the C++ compiler (c++  ) is a cross-compiler... no
checking whether we are using GNU C++... yes
checking whether c++ accepts -g... yes
checking how to run the C preprocessor... gcc -E
checking for ANSI C header files... yes
checking for string.h... yes
checking for main in -lXbsd... no
checking for socket in -lsocket... no
checking for gethostbyname in -lnsl... yes
checking for dcgettext in -lintl... no
checking for getnodebyname in -ldnet_stub... no
checking that c++ can handle -O2... yes
checking standard STL is available... yes
checking for tcl.h... configure: error:
/nfs/ruby/haldar/conser/tcl8.3.2.linux/ is not a directory
Ns configuration failed! Exiting ...

Can anyone help me with it?

Thanx
yingjie