If you tried JOGL with JDK 1.5 on Linux and got an exception saying that it can’t fiind libmawt.so then you can do the following workaround:
Copy libmawt.so from ${JAVA_HOME}/jre/lib/i386/motif21/libmawt.so to ${JAVA_HOME}/jre/lib/i386/libmawt.so (one level higher)
OR
add ${JAVA_HOME}/jre/lib/i386/motif21/ to the environment variable LD_LIBRARY_PATH.
This bug is fixed in beta2.