Hi friends...I tried to play a media file by scheduling a cron job......it says the following error...can any one decode and tell the problem........

From gokul@localhost.localdomain Mon Dec 22 12:14:02 2008
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From: root@localhost.localdomain (Cron Daemon)
To: gokul@localhost.localdomain
Subject: Cron <gokul@localhost> realplay /media/BACKUP/Yuvraj/02 Track 2.mp3
Date: Mon, 22 Dec 2008 12:14:01 0530 (IST)
Content-Type: text/plain; charset=UTF-8
Auto-Submitted: auto-generated
X-Cron-Env: <SHELL=/bin/sh>
X-Cron-Env: <HOME=/home/gokul>
X-Cron-Env: <PATH=/usr/bin:/bin>
X-Cron-Env: <LOGNAME=gokul>
X-Cron-Env: <USER=gokul>


** ERROR **: Unable to open display
aborting...
/usr/bin/realplay: line 57: 25666 Aborted $HELIX_LIBS/realplay.bin "$@"

Crontab has a very limited environment and overall it does not allocate a display. You have to explicitly allocate it by assigning the DISPLAY environment variable, but this assumes you previously know which display number is active on your monitor (usually :0.0). For example a working cron job can be:
For more complex tasks you have to play with the xauth command.

You could use mpg123 or mplayer, it doesn't need X
mpg123 /media/BACKUP/Yuvraj/02 Track 2.mp3