[USR-TC] ARC as router to NMC

Hello! I have 5.3.3 ver. of firmware installed to Hiper ARC and 6.1.17 ver. installed to NMC (16Mb, 486SX). Can I ping NMC through Hiper ARC? if I can what do I have to configure? At present I cant do it.... But I was able to ping before upgrade firmwares. 10x in advance, Murad