Most brokers won't provide shorting as an option to stocks under something like $1/sh or $5/sh. I am not sure what's common. To short Penny Stocks you have to use specific brokers that work in this area. URL's have for them been posted here in the past (or maybe RB) but I don't recall who they are now.
It's simply a specialty are that requires a broker set-up for it.
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