December corn has already rallied $1 from the low.  The time to put calls on is when the trade has been beating the market down not when most of the trade has turned bullish.

You will lower your hedging price by the premium paid if the December corn contract closes below $4.50 on 11-26-10.

Looks like your potential gain is .35  (.5-.15) of course minus commissions.

To me it is not worth it.  If you sold it at a price you were happy with why not wait for the spread to widen (if they do) and then roll your dec hedge out to the March thru July and deliver the corn. 

Your situation is your own do what you please.

Andy