asanal wrote on Feb 8^th, 2013 at 4:43pm:

I thought so too. Every time when I go through clouds. Airspeed probe frozen. Manually I continue to climb. Even throttle open full and N1 shows full power. 777 receives stall warning and plane plunges from 320FT to ocean .It looks like coding logic connected to airspeed indication rather the power setting in this scenario.(?) :-/

Happened to me too; plunged into the Serengeti, Tanzania. Now I routinely press SHIFT+H on entering the runway, and all anti-ice switches to ON anytime SAT temp (FMC PROG page 2) <10C and heading into clouds. Solves the problem for me. Till its hardcoded as CS plan to do by the looks of things.