A number of people have been very helpful in preparing Rgraphviz 2.

From the Graphviz developers email list
  Stephen North
  Emden R. Gansner
  Gordon Smith

Help with the R package, extensive testing and building
  Dan Tenenbaum

Emotional support
  Martin Morgan

Testing and bug reporting
  Laurent Gautier
  Roger D Peng
  Thomas Cokelaer
  Henrik Bengtsson
  Mike Jiang
  Adi Tarca
  David Meyer
  Mikko Korpela
  Claus Bendtsen
  Jitao David Zhang
  Klaus K. Holst
  Anand Gavai
