....rather than recreating the wheel, I will point you to a previously published solution here it appears to change both NT and Unix passwords but I suspect you can just strip out what you need, modifying the  waitfor() to account for your prompts.

In reply to Re: telnet, passwords, and other challenges to my cough syrup ridden mind by phydeauxarff
in thread telnet, passwords, and other challenges to my cough syrup ridden mind by jcpunk

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