installing kdiff3 without KDE

[perryh at pluto.rain.com]

According to its README, kdiff3

   provides special support for KDE3, but it can also be
   built without KDE3 if the Qt-libraries are available.

How do I get the port to do this?  I keep getting errors claiming
that KDE is not installed correctly -- which is true, it's not
installed at all -- and I haven't been able to puzzle out how to
hack around them.  (I do have qt33 installed.)  There don't seem
to be any "make config" options, but perhaps there is a knob that
can be specified when running make?