There seems to be no Debian packages for XOTcl. The installation instruction of XOTcl mentioned TCL sources are a must. Many people will put-off installation because of these points.

Things are not that complex.Here is a instruction to get it going.

Actually TCL headers are required, not full source files.

Debian packages required - tcl package and tcl-dev package. tcl-dev is required if you want to compile any C based extension for Tcl.

In my case, 
 apt-get install tcl8.4
 apt-get install tcl8.4-dev

I assume the required packages for compiling C code are present. 
(someone please mention, if required).

Get the source code from xotcl website.

let us say you had downloaded xotcl_xx.tar.gz to '/var/downloads'
 
 cd /var/downloads 
 tar xvzf xotcl_xx.tar.gz
 cd /var/downloads/xotclxxx
 ./configure --with-actiweb --with-tcl=/usr/lib/tcl8.4
 make

Now you will have libxotclxxx.so in /var/downloads/xotclxxx

Now copy that (*.so) into you desired directory and play with xotcl.
let us say , the desired directory is /var/devl/tcl.

 cp /var/downloads/xotcl_xx/libxo*.so /var/devl/tcl
 cd /var/devl/tcl
 tclsh
 load ./libxotclxxx.so
 namespace import xotcl::*
 object junk
 junk destroy

The above approach makes it easier for me to have xotcl in any desired machine.
Just copy the libxo*.so
 
If one prefers the lib in standard directories
 cd  /var/downloads/xotcl_xx
 make install

Then typical tcl session would be
 tclsh
 package require XOTcl
 namespace import xotcl::*

for more info
[xotcl for prototyping]