HELENA, Mont. (AP) - The Montana Supreme Court has denied the appeal of a man once accused of plotting to kidnap David Letterman's young son from Letterman's ranch in Montana.

The 2005 kidnap-related charges against Kelly Frank were ultimately dismissed, but Frank was sentenced to 10 years in prison for overcharging the talk show host for painting work at his ranch.

Frank escaped from a state prison ranch in June 2007 and was recaptured six days later. He was given an additional 10 years for the escape.

The 47-year-old Frank appealed his escape conviction to the state Supreme Court, which on Tuesday affirmed the conviction.

Prison spokeswoman Linda Moodry says Frank will be eligible for parole in May 2011.

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