[CMake] Cmake chained conditionals

[alaterale at elitemail.org]

Hi,
I have another question I hope someone can help me with.  I've been
trying to translate an older ant style build doc to cmake, but one thing
seems to be missing from cmake that maybe I just don't know how to
access.

IF(NOT ${VAR1} AND NOT ${VAR2} AND NOT ${VAR3})
...
This doesn't work, and I can't find a way to make it work like that.  I
see in the docs that it says that its only limited to 2 variables, but
that doesn't make much sense.
"True if both variables would be considered true individually. Only one
AND is allowed to keep expressions short."
Is there a way to get this switched back on so I can do statements like
above?  The same thing for OR as well.
Thanks!
~~JS