openjdk-6-jre-zero 6b22-1.10.1-0ubuntu1 (amd64 binary) in ubuntu natty

 The package provides an alternative runtime using the Zero VM and the
 Shark Just In Time Compiler (JIT). Built on architectures in addition
 to the Hotspot VM as a debugging aid for those architectures which don't
 have a Hotspot VM.
 .
 The VM is started with the option `-zero'. See the README.Debian for details.