Felicity also revealed Marc had to force himself to keep away from the set because he was afraid he would inadvertently let the news slip to Felicity and her co-stars Teri Hatcher, Marcia Cross and Eva Longoria before the official announcement.
She said: "He can't seem to keep his mouth shut so he had to keep himself away from set."
Meanwhile, Dana Delaney is hoping to reprise her role of Katherine Mayfair - who left for Paris in season six with her lesbian lover Robin Gallagher (Julie Benz) - so viewers will find out what happened to Katherine after she left Wisteria Lane.
She said: "I would love to come back for one episode just to sort of wrap things up with Katherine. I want to know that she's happy. A happy lesbian. Wouldn't that be nice?"
However, rumours that Nicollette Sheridan - who is suing Marc for £12 million over unfair dismissal claims - could return in the final episode as man-eater Edie Britt were dashed as when Nicollette was asked if she would make a cameo she replied "Edie's dead".
- BANG! Showbiz