Just attempted to run qcad and got an error as follows

[me@mypc qcad-2.2.2.0-1-prof.linux.x86]$ ./qcad 
./qcad: error while loading shared libraries: libXrandr.so.2: cannot open shared object file: No such file or directory

Found that my 64 bit version of libXrandr on Fedora 15 wouldn't do it for qcad.

[me@mypc qcad-2.2.2.0-1-prof.linux.x86]$ locate libXrandr
/usr/lib64/libXrandr.so.2
/usr/lib64/libXrandr.so.2.2.0
/usr/share/doc/libXrandr-1.3.1
/usr/share/doc/libXrandr-1.3.1/AUTHORS
/usr/share/doc/libXrandr-1.3.1/COPYING
/usr/share/doc/libXrandr-1.3.1/ChangeLo

So navigated to my local Fedora Mirror and grabbed the 32bit version and installed it

wget http://mirror.optus.net/fedora/linux/releases/15/Fedora/i386/os/Packages/libXrandr-1.3.1-2.fc15.i686.rpm
rpm -ivh libXrandr-1.3.1-2.fc15.i686.rpm

# you have it right when you have libXrandr in /usr/lib as well as lib64.
find /usr -name libXrandr.so.2
/usr/lib64/libXrandr.so.2
/usr/lib/libXrandr.so.2