SCP / SFTP Auto login is very SLOWwwwwwww~~~!!

Dear All,

I have setup a SFTP Server (using SSH Tectia) in Windows, and running a
script to copy some files to a Solaris 8 box (using OpenSSH).

All the keys and users authentication are setup correctly, so that the
SFTP can login without prompting for a user name / password.

However, the problem is the Auto login is very slow. It took about 13
sec to login.

The two machine is put under a same subnet with very low traffic. I
can't find any option to disable reverse DNS lookup in SSH Tectia. So
what could have gone wrong?

TIA.

.