I have seen and used a few different ways on setting up Greek Spelling on Vim. This is an easy one
Get it
# wget http://ftp.vim.org/pub/vim/runtime/spell/el.utf-8.spl
Move it to the appropriate place --usually the following
# mv el.utf-8.spl /usr/share/vim/vim72/spell/
Use it
# vi test-greek-spelling :setlocal spell spelllang=el
on some systems you just need to type
:setlocal spell spelllang=elin Normal Mode as root and the downloading and installation of the Greek MySpell will happen auto-magically
Some related resources:
OpenOffice Greek Dictionaries
ftp.vim.org Greek Spell Checking Recipe
vim README_el.txt (use ISO-8859-7 to see the Greek Characters )
vim Myspell
a few ways to generate a spell
and of course ispell.math.upatras.gr
Vim Greek Spell Checking