Do you ever have problems displaying vi in the xterm or cmdtool windows? Your EDITOR variable may have not been set correctly. Here is a simple fix.
Bourne shell:
# sh
# EDITOR=vi; export EDITOR
C shell:
# csh
# setenv EDITOR vi
I had to use these procedures today because I was having problems displaying text the crontab with crontab -e.
By the way, you can add this type of information into your initialization files ($HOME/.cshrc, $HOME/.kshrc, $HOME/.profile, etc).