QNX host cannot ping SCO host, vice versa

The problem I am facing now is that the QNX host could not ping the SCO host and vice versa. They are in the same domain, ie, 172.20.3.xx. As I am very new to Unix, I guess I must have missed out some important steps. Pls help... Thanx alot

Check your routing tables to insure they are set up correctly.

Thank you Neo for your reply, the equipment is now back to the vendor, cheers!