When worked on packages for RHEL7 a line:

CLASSPATH="lib"

has been replaced by:

if [ ! -z "$CLASSPATH" ]; then
        CLASSPATH="$CLASSPATH"
fi

which is actually wrong, should be reverted.
Even more, those lines actually do nothing useful.

Now logback cannot find default log file because:

3. If no such file is found, it checks for the file logback.xml in the classpath..

http://logback.qos.ch/manual/configuration.html

Another point - I don't see JAVA_OPTIONS="-server" line in RHEL7 packages, which also not very good, should be returned!
See http://stackoverflow.com/questions/198577/real-differences-between-java-server-and-java-client