vi has always followed my terminal size, so I doubt a bit .. unless you had it configured for a certain size or terminal type and you are using something else� look if you have a .exrc in your home directory and if so what is its content?
This happens to me all the time on Solaris. I physically resize my window to make it smaller and then retry the vi command. It always works with the second try with the smaller window. It might be possible to get to run in a too-large window by artifically ignoring the surplus columns but that would lead to weird editing experience.