Playing a normal game with no mods loaded and after some minutes playing at random intervals I will see "WARNING: updateListener: invalid value" and the game stalls, no movement and a restart needed to fix it and even then I have to issue a /teleport 0,10,0 command to get things moving again...
Any ideas why this happens ? Am using minetestc55_201307312348-0~2168~raring1_i386 on Lubuntu 13.04 running an an Intel Atom 1.8 Dual with 2GB memory and Ion v.2 graphics...