Updates to this story
Rajaratnam is on trial for insider dealing while Goel was a government witness.
Rajaratnam asks Goel about the investment team involved. All this happens months before it was publicly announced.
The pair talk about investors agreeing to put as much as $3.5 billion in the transaction, code-named "Project Rain."
Rajaratnam's defence teams say that the tapes "prove "nuttin"" and there were loads of industry rumours circulating about the deal at the time.
According to the New York Post, Goel is expected to take the stand today to testify against his former mate.