Font copyright infringement?

This question may be hopelessly naïve, but I am very poorly versed in
software legalities:

If I were to modify a copyrighted font (say, one designed by Monotype) and
redistribute it *while retaining the original copyright*, would I be in
violation of some kind of law? Would I be likely to be sued? What's the deal
here?

I ask this because I'm feeling at present somewhat rattled about the severe
paucity of Native American fonts available on the web. It seems that most of
those that exist are extremely badly designed and mapped (I ran into a
Navajo font today in which the ogonki WERE GOING IN THE WRONG DIRECTION --
how could any font designer do such a thing with a clear conscience?!). I
would *love* to modify a bunch of families and make them generally available
for the well-being of all mankind, but we mustn't infuriate the corporate
lawyers...

My immense thanks for any help that the knowledgeable can send my way!

-Josh

----------
Josh Brandt-Young <vionau@...>
"After the tempest I behold, once more, the weasel."
(Mispronunciation of Ancient Greek)

Replies