I've assigned a dff to a object(1645 ,some weird bed ) and then done the next thing:
local fgt = createObject ( 1645,-810.13623046875, 2535.4724121094, 96.055953979492 -0.7, 0, 0, 0 )
setObjectBreakable(fgt, false)
problem is , the object still evaporates(some small spark in the middle of some really white smoke , probably from the shaders I'm using) after 1 hit .