I'm sorry, probably I was too hasty to submit this... After using 2.5G of swap, povray 3.6.1 is (extremely slowly) able to render my file. megapov ist a fork of povray 3.5 and probably thus more modest, and that old Mac has to have both a clever swap mechanism and a good graphics processor. Still I think, my machine is slower than it should be, but that's probably not a bug...
signature.asc
Description: This is a digitally signed message part
