Oncogenic mutations?

[Agnar Sturla Helgason]

I wonder if someone could help me with a small problem. I'm writing an essay
on oncogenes and cell transformation and there is one thing I find unclear
in the references I am using. According to the 2nd edition of The Cell 
(Alberts & co.) oncogenic mutations are always dominant, while tumor 
suppressor gene (anti-oncogenic) mutations are always reccesive. Another 
reference seems to indicate the possibility of recessive oncogenic mutations 
(this could be a misunderstanding on my behalf). 
Can an oncogenic mutation be reccesive? And if not, why?

                                  Agnar Helgason, Iceland.