Net::NNTP

I am trying to get a list of News Groups using Perl, however I get the 
following error, when I try either list(), newsgroups(), or the active () 
functions.

Can't call method "active" on an undefined value at ./getnntp.pl line 11.

#!/opt/local/bin/perl
use Net::NNTP;
$nntp = Net::NNTP->new("news.microsoft.com",Debug,1);
$DATE=$nntp->date;
$GROUP=$nntp->group;
($narticles,$first,$last,$GROUP)=$nntp->group("microsoft.public.access");
$XOVER=$nntp->xover(19303);
$LIST=$nnpt->list;
$nntp->quit;  

The other functions group,date and xover work fine.

Thanks,
GeneMat