Arun,
you should check if OTM tries to send the email now. Either check the logs of your Exchange server, or have a look at the network communication.
The latter helped me a lot. To do this, install wireshark (
www.wireshark.org) on your OTM machine and have it filter for SMTP communication. Then you can see what OTM tries to do.
A side note: The email address you use for trying should be valid on your exchange box. Many email servers allow only outgoing mail from known users. You might also need exchange configuration to allow your OTM box to send mail via SMTP.