Error if (!isdefined(level._effect["lantern_light"]))

[Mariusz]

******* script runtime error *******
undefined is not an array, string, or vector: (file 'maps/mp/_load.gsc', line 113)
if (!isdefined(level._effect["lantern_light"]))
*
called from:
(file 'maps/mp/_load.gsc', line 12)
lanterns[i] thread lanterns();
*
called from:
(file 'maps/mp/bz_drewe.gsc', line 3)
maps\mp\_load::main();
*
started from:
(file 'maps/mp/bz_drewe.gsc', line 1)
main()
*
************************************
quitting...