Some FTP sites will allow you to change password. After you enter the User ID. Change the password as follows.
At the "Password:" prompt you would put the oldpassword:newpassword:newpassword.
You will not be able to see anything you type so you have to make sure you type it correct.
password:(oldpass):(newpass):(newpass)
This works for one of my clients. I cannot confirm it works on all FTP clients.
Thanks