The FAA is expected to issue the first Airworthiness Directive on the Eclipse 500 VLJ in the next few days, restricting the jet to day VFR flight because of a pitot/angle-of-attack probe freezing problem that occurred on three flight-test airplanes. Until the AD becomes effective, the Eclipse 500 can be flown IFR but not in IMC, pending installation of a pitot tube fix. The problem took place after takeoff in high-humidity conditions. Moisture inside the pitot tube froze at high altitude, trapping air pressure in the air data computers and shutting down airspeed indications on the primary flight displays, then melting after descent into warmer air. Eclipse has flight tested a new pitot/AOA probe for more than 60 flights and expects certification of the new probe in mid-July. The new tube has a drain in the probe tip, added insulation, new heat-conductive material and a new interior heater. A pitot line drain task will be added to the 300-hour maintenance interval.