sftp client in interactive mode

[hari at isofttechindia.com]

Hi,
  I work on openssh-2.9p2 installed on LynxOS i386
system. sshd, ssh, scp and sftp-server all work fine.
The problem is sftp client, in interactive mode, exits
after authentication printing the sftp prompt. sftp
client works fine in non-interactive mode.
i.e.,
lynxos>sftp hari at linuxsystem:test
works fine
But,
lynxos>sftp hari at linuxsystem
...
sftp>
lynxos>
Any help, as to why sftp exits in interactive mode.
-Hari.