As documented in the Jikes RVM userguide, 
  http://jikesrvm.org/Building+the+RVM
on Debian based platforms, you have to install the ant-optional
package to build Jikes RVM.  

Quoting from the user guide at that URL

  Jikes RVM requires a complete install of ant, including the optional
  tasks. These are present if you download and install ant
  manually. Some Linux distributions have decided to break ant into
  multiple packages. So if you are installing on a platform such as
  Debian you may need to install another package such as 'ant-optional'.

This is a trivial install of standard software to get a sane build
environment, not something specific to the research results of the
OOPSLA'12 paper. It is a basic step for building Jikes RVM on the
platform and well-documented in the Jikes RVM userguide.