Orenair B738 at St. Petersburg on Sep 12th 2014, cabin did not pressurize

An Orenair Boeing 737-800, registration VP-BEN performing flight R2-3515 from Saint Petersburg (Russia) to Monastir (Tunisia), was climbing through FL260 when the crew stopped the climb due to problems with the cabin pressure, descended the aircraft to FL100, entered a hold to burn off fuel and returned to St. Petersburg for a safe landing about 2 hours after departure.

A replacement Boeing 737-800 registration VQ-BSR reached Monastir with a delay of 4.5 hours.