How to get the remote cable release to work on my Nikon D70s?

Just purchased the MC-DC1 remote cord for my Nikon D70s. I want to take some photos of the stars moving at night but I can't get the cable release to hold the shutter open. It will cause the camera to close it's shutter and take a picture but it won't hold it open for longer than 30 seconds. Could someone help me out and tell me what kind of settings my camera should be at to get this to work?

Thanks!

Added (1). I did read the user manual… It has three steps to it - find where to plug it in, plug it in, hold button. I have used the lock function of the cable release but the shutter still closes at 30 seconds even if I still have the cable release locked or am holding it down.

The The MC-CD1 can be locked for long exposures

Me thinks you need to read the user manual

http://www.nikonusa.com/...s-Overview

Shutter speed is set to 30s. The cable is working. Set shutter speed to Bulb (or set mode dial to Bulb whichever the case may be with your camera). Yes, you may have to check it up with the manual again. Use a watch to time your shot. Release shutter lock from cable when done.

http://keerok-potd.blogspot.com/2012/02/polaris.html

You need the camera in M mode and the shutter speed set to "B"

Put your camera into BULB mode.