When configuring sipXecs in an HA setup, the master will send over configuration files that contain file paths to 32bit shared libraries. You will need to create symlinks to honor the file paths on the 64bit machines.
ln -snf /usr/lib64/authplugins /usr/lib/authplugins
find /usr/lib64 \
\( -name 'libRedirector*.so' -o -name 'libRegistrar*.so' \) \
-exec ln -snf {} /usr/lib \;