But not to worry. it has been replaced with an SSH server, which has a much higher level of security while offering the same functionality. You should download two applications to utilize SSH: putty and WinSCP. Putty replaces telnet and will let you get a command line login to kahuna. WinSCP will give you an interface similar to WS_FTP but at a much higher level of security.
WinSCP can be found here: http://winscp.sourceforge.net/eng
Putty (and make sure to download version 0.58 or later) can be found here: http://www.chiark.greenend.org.uk/~sgtatham/putty
As stated, putty will give you remote command line login access. Also it has a better telnet interface than the standard Windows telnet client. You can find a brief putty tutorial that describes how to use putty for remote access.
To jumpstart using WinSCP take a look at this online tutorial for getting started. Simply put kahuna.clayton.edu in the host field of the WinSCP login dialog to connect to kahuna. Also be sure that the port listed at the bottom of the dialog is set to 22.
Hope this helps,