/usr/lib64/gcj-4.1.1/bin/gjar: /usr/lib64/gcj-4.1.1/bin/gjar: cannot execute binary file
 * build ecj with bootstrapped ecj
Exception in thread "main" java.lang.NoClassDefFoundError: org.eclipse.jdt.internal.compiler.batch.Main
   at gnu.java.lang.MainThread.run(libgcj.so.7)
Caused by: java.lang.ClassNotFoundException: org.eclipse.jdt.internal.compiler.batch.Main not found in gnu.gcj.runtime.SystemClassLoader{urls=[], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}
   at java.net.URLClassLoader.findClass(libgcj.so.7)
   at java.lang.ClassLoader.loadClass(libgcj.so.7)
   at java.lang.ClassLoader.loadClass(libgcj.so.7)
   at java.lang.Class.forName(libgcj.so.7)
   at gnu.java.lang.MainThread.run(libgcj.so.7)

!!! ERROR: dev-java/eclipse-ecj-3.3.0_pre4-r3 failed.
Call stack:
  ebuild.sh, line 1611:   Called dyn_compile
  ebuild.sh, line 968:   Called qa_call 'src_compile'
  environment, line 4909:   Called src_compile
  eclipse-ecj-3.3.0_pre4-r3.ebuild, line 74:   Called die

!!! ecj build failed!
!!! If you need support, post the topmost build error, and the call stack if relevant.
!!! A complete build log is located at '/var/tmp/portage/dev-java/eclipse-ecj-3.3.0_pre4-r3/temp/build.log'.

!!! When you file a bug report, please include the following information:
GENTOO_VM=  CLASSPATH="." JAVA_HOME="/etc/java-config-2/current-system-vm"
JAVACFLAGS="" COMPILER=""
and of course, the output of emerge --info
!!! This ebuild is from an overlay: '/usr/local/java-gcj-overlay'