Editor's note: The following are questions received from listeners of "RealMoney Radio." To send Cramer a question about topics from his radio show, click here. Listen to Cramer's latest radio show by clicking here.

What do you think of the Vonage IPO?-- Matt from New York

Jim Cramer

: I believe the story of Vonage can take the stock up after the IPO, but I wouldn't be in a big rush to buy it. The company isn't profitable, and the telcos and cable companies have very aggressively moved into VoIP, which is Vonage's specialty.

I believe VoIP pricing will only go down in the future, and Vonage will need a huge amount of customer growth to become profitable.

Is Hansen (HANS) a short?-- Gregory from California

Jim Cramer

: First of all, I am not allowed to short stocks per my deal with CNBC, the station that airs my "Mad Money" show. I would not be shorting Hansen here anyway, especially now that they've inked a distribution deal with


(BUD) - Get Report

. But even outside of the BUD deal, Hansen is still a heavily shorted stock, which sets up the possibility for an extension of the short squeeze that has been running for over 100 points now. Energy drinks may be a fad, but shorting stocks based on expectations that a fad will end is dangerous.

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