Maybe that's why they were doing so well? If they didn't pay for $5 mill of software when they started up, that's a lot less startup capital they needed and profits come all that much quicker.
I think that it could be probable that they were sold down the river by the phone companies who are desperate to get rid of Vonage by turning them in to the Software Piracy commission.
However, it should be noted that they are "under investigation" which means that they may be the subject of a vicious rumor...and it isn't true. Have to give them the benefit of the doubt until it's proven one way or the other.
The CEO Citron was fined $22.5 million dollars. He has obviously made a ton of money of of E-Trade. I am sure he will have no problem swallowing another $5 million.