On March 13, 2003, about 1015 eastern standard time, a Dornier 328-300, N419FJ, sustained minor damage during a lightning strike, while descending near Wellman, Ohio. The airplane was operated by Atlantic Coast Airlines Inc., as Delta Connection flight 6278. There were no injuries to the 3 crewmembers and 12 passengers. Instrument meteorological conditions prevailed for the flight that originated from Toledo Express Airport (TOL), Toledo, Ohio; destined for Cincinnati/Northern Kentucky International Airport (CVG), Covington, Kentucky. An instrument flight rules flight plan was filed for the scheduled air carrier flight conducted under 14 CFR part 121. The captain stated that the flight was cleared to cross the TIGRR intersection at 11,000 feet msl, on the CINCE FOUR ARRIVAL into CVG. The airplane was flying through light rain, and then heavy rain as it passed over TIGRR. At that time, the captain asked air traffic control (ATC) for a 20-degree right turn due to weather. The deviation was approved, but soon after turning to the new heading, the airplane was struck by lightning. After the lightning strike, all five display units and the flight management system (FMS) failed. The first officer then declared an emergency to ATC. Soon after, display units four and five reactivated, and the flight crew was able to restore display units one, two, and three, but not the FMS. ATC vectored the flight to the ILS Runway 36 approach to CVG. The flight landed uneventfully, and taxied to the gate. Review of weather radar revealed light to medium intensity echoes near CVG about the time of the incident. The reported weather at CVG, at 1018, was: wind from 050 degrees at 6 knots; visibility 3/4 mile in mist and light rain showers; a scattered cloud layer at 600 feet, a broken cloud layer at 1,300 feet, and an overcast cloud layer at 4,300 feet; temperature 46 degrees F; dew point 46 degrees F; altimeter 29.94 inches Hg. Examination of the airplane revealed an approximate 12-foot section of skin had separated from the upper portion of the rudder. However, during the flight, the captain did not experience any control problems with the airplane.