fixed https://code.google.com/p/heekscnc/issues/detail?id=359
fixed https://code.google.com/p/heekscnc/issues/detail?id=359
satovey/heekscnc,satovey/heekscnc,asmuelle/heekscnc,jihyun-kim/heekscnc,jihyun-kim/heekscnc,jihyun-kim/heekscnc,asmuelle/heekscnc,asmuelle/heekscnc,satovey/heekscnc,asmuelle/heekscnc,jihyun-kim/heekscnc,satovey/heekscnc