The Lufthansa web site says that in-cabin pets must weigh less than 8 kg (including the carrier) and the maximum dimensions of the pet's carrier are 55 cm x 40 cm x 20 cm (21.7 inches x 15.75 inches x 8 inches).
How strict are they about enforcing this limit, for soft-sided (squishable) carriers?
[cross-posted: http://www.flyertalk.com/forum/travel-pets/1270999-lufthansa-cabin-pet-policy.html ]