Frail has seen speculation over the future of skipper Berra increase after Wolves boss Mick McCarthy attended the 4-0 home defeat by Rangers back in February.
But he insists he is keen to keep the defender at Tynecastle and claims there has been no direct contact from the Molineux outfit.
Frail told the Evening News: "I know Mick McCarthy was at the game against Rangers but whether he was there to watch Christophe or not, I don't know.
"When our players are doing well, there's obviously going to be interest in them. I think it's just a sign that your players are doing their jobs.
"He's done well recently and we wouldn't want to lose him."