When wmake some applications of OpenFOAM, there is a problem:

……
/usr/bin/ld: skipping incompatible /home/abc/OpenFOAM/OpenFOAM-1.3
/lib/linuxGcc4DPOpt/libfiniteVolume.so when searching for -lfiniteVolume
/usr/bin/ld: cannot find -lfiniteVolume
collect2: ld returned 1 exit status
make: *** [/home/abc/OpenFOAM/OpenFOAM-1.3
/applications/bin/linuxGcc4DPOpt/icoFoam] Error 1

I find the solution on the OpenFOAM Discussion: if the architechture is x86_64, the environment variable $WM_64 should be turned on, which can be set as export WM_64=on in the OpenFOAM bashrc file.

Afterwards, there still is another problem:

…
/usr/bin/ld: cannot find -liberty
collect2: ld returned 1 exit status
make: *** [/home/abc/OpenFOAM/OpenFOAM-1.3/
applications/bin/linuxAMD64Gcc4DPOpt/icoFoam] Error 1

Also, there is a solution on the OpenFOAM Discussion: GNU binutils-devel package should be installed, because liberty is one of the function of binutils package.

(Tested on Fedora Core 6)