[grbl Issue#1251] And again … compilation error.

Take this: https://github.com/grbl/grbl
Add as a library – OK!
Compile for Uno or for Mega :
Servo\avr\Servo.cpp.o: In function _vector17':
C:\Program Files (x86)\Arduino\libraries\Servo\src\avr/Servo.cpp:81: multiple definition of _vector17′
grbl\stepper.c.o:C:\Users\Џ®«м§®ў вҐ«м\Documents\Arduino\libraries\grbl/stepper.c:282: first defined here
c:/program files (x86)/arduino/hardware/tools/avr/bin/../lib/gcc/avr/4.8.1/../../../../avr/bin/ld.exe: Disabling relaxation: it will not work with multiple definitions
C:\Users\73B5~1\AppData\Local\Temp\build6073462420989878416.tmp/core.a(wiring.c.o): In function _vector23':
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/wiring.c:49: multiple definition of _vector23′
grbl\stepper.c.o:C:\Users\Џ®«м§®ў вҐ«м\Documents\Arduino\libraries\grbl/stepper.c:186: first defined here
collect2.exe: error: ld returned 1 exit status
Ошибка компиляции.

Whats wrang. Thanks in advice.