'tty' Issue of Apache Mina SSHD

[Ma, Qiang (Mark)]

Hi,
               I got a problem with using Mina SSHD. I used 
clientSession.createExecChannel("sudo su someuser")  , the stderr from remote 
server was "sudo: sorry, you must have a tty to run sudo".
               How can I create pseudo-teletype to successfully "sudo su 
someuser" and execute continuous commands?
               I am looking forward to your reply.

Thanks
Mark