Norton Live Update stopped connecting ....

Hi everybody,
    I am in a strange problem, I have Norton antivirus 2003. Now it has stopped updating my virus definitions. Actually when I run the Norton Live Update it responds like this....

Live Update Status.

The following Symantec products and components are installed on your computer.
> LiveReg
> LiveUpdate
> Norton AntiVirus
> Norton AntiVirus Virus Definitions
> Norton CleanSweep
> Norton Ghost
> Norton SystemWorks 2003
> Norton Utilities
> ScriptBlocking
> Speed Disk
> Symantec Common Client Updates
> Symantec Common Driver: SymEvent
> Symantec Redirector
> Symantec Security Response Submission Software Updates
> Symantec Shared Components

Initializing...
Connecting to liveupdate.symantecliveupdate.com...
Downloading catalog file, not available.
Connecting to liveupdate.symantec.com...
Downloading catalog file, not available.
Unable to connect to host
LiveUpdate could not retrieve the catalog file of available Symantec product and component updates. Please verify that you are able to connect to the Internet and run LiveUpdate again.
LiveUpdate session is complete.

I simply cannot understand what to do...Please help...It's urgent.

Thanks in advance,
Avik.