[ns] After to have installed ns-2.1b5...

["paolo.tegon@libero.it"<paolo.tegon@libero.it>]

Good morning.
After the command ./install I can read:

Please put ../ns-allinone-2.1b5/bin into your PATH environment.
Please put ../ns-allinone-2.1b5/otcl-1.0a4 into your LD_LIBRARY_PATH 
environment!

This means that I have to write in .bash_profile this lines:

PATH=$PATH:$HOME/root/../ns-allinone-2.1b5/bin:
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$HOME/root/../ns-allinone-2.1b5/otcl-
1.0a4

Is it true?
If it is false, where I have to write this lines?

Paolo.