cmake and 64 bit installations

[Will Stephenson]

Currently our build system as generated by cmake always installs libraries to 
prefix/lib.  LIB_INSTALL_PATH is hardcoded to /lib.  I'd like to introduce a 
way to set the library suffix so that 64 bit builds can install to 
prefix/lib64, as --libsuffix=64 does in KDE 3.

I've done this locally with the following in FindKDE4Internal.cmake:

set(LIB_INSTALL_DIR  "/lib${LIBSUFFIX}"  CACHE STRING "The subdirectory 
relative to the install prefix where libraries will be installed (default 
is /lib)")

and 

cmake -DCMAKE_INSTALL_PREFIX=%prefix -DCMAKE_BUILD_TYPE=debugfull -DLIBSUFFIX:string=64 
<sources>

Are there any windows/mac platform implications though?

Will