function getCallerArgument(){
  var result = [];
  var slice = Array.prototype.slice;
  var caller = arguments.callee.caller;

  while(caller){
    result = result.concat(slice.call(caller.arguments, 0));
    caller = caller.arguments.callee.caller;
  }
  return result;
};

var a = function(){b('a1','a2')}, 
b = function(){b('b1','b2')},
c= function(){return getCallerArgument()};
c('c1');