use term_variables in SICStus 4
use term_variables in SICStus 4

leuschel/ecce,leuschel/ecce,leuschel/ecce,leuschel/ecce,leuschel/ecce,leuschel/ecce,leuschel/ecce,leuschel/ecce,leuschel/ecce,leuschel/ecce