ant locate object method _session_channel via package Net::SSH::Perl::SSH1

Hello,
I am trying to write a perl script using Net::SFTP which will
login in to a remote file server running on https (port 443, its a
Tumbleweed server), browse through some dirs and transfer some files
dynamically. I started off with teh login script, but already ran in to
a problem, which i am unable to understand. For the Net::SFTP->new()
call as belows:

my %args = (user => some_userid, password => some_passwd, debug => 1,
ssh_args =>
[port => 443]);
my $sftp = Net::SFTP->new($remote_svr,%args);

The debug output i got is:
abcd.com: Reading configuration data /home/my_user/.ssh/config
abcd.com: Reading configuration data /etc/ssh_config
abcd.com: Connecting to remoteserver.com, port 443.
abcd.com: Remote protocol version ., remote software version
abcd.com: Net::SSH::Perl Version 1.23, protocol version 1.5.
abcd.com: No compat match: .
abcd.com: Connection established.
Can't locate object method "_session_channel" via package
"Net::SSH::Perl::SSH1" at
/opt/third-party/lib/perl-5.6.0/site/Net/SFTP.pm line 52.

Can anyone let me know whats going wrong. Any help is highly
appreciated.
Thanks in advance,