The pilot stated that he was practicing takeoff and landings,and that during the last landing, the airplane encountered a gust of wind. The tail-wheel equipped airplane then veered right and the pilot's efforts to correct the veer were unsuccessful, resulting in the airplane departing the runway surface. The airplane subsequently impacted a ditch, sustaining substantial damage to the engine firewall and fuselage. The pilot added that there were no pre-impact mechanical malfunctions or failures with the airplane.