LinuxQuestions.org - using notify-send

When I use notify-send in scripts run by using '/etc/crontab' notifications are not displayed in Hardy.
In gusty doing the following

Code:

DBUS_SESSION_BUS_ADDRESS="dbus session address of the user" sudo -u "user" notify-send "Some text"

displays notification but when I use this in Hardy I get the following error

Code:

libnotify-Message: Unable to get session bus: Failed to connect to socket /tmp/dbus-'some random text': Connection refused

Is there any other way to make scripts executed by '/etc/crontab' display notifications in Hardy?