Help with linuxxdoom, Gives me an error... Options

[NeptuneNavigator...]

Hello; I have a problem when trying to run linuxxdoom. I'm new to Linux (of course), but since I'm running KNOPPIX 5.01, with kernel - aw, heck, what's the number - I know enough to get by. I have to type this in Windows because my browser in KNOPPIX isn't set up yet to properly accept cookies. Anyway... I'm trying to make a permanent new home in KNOPPIX, with Windows 98SE on the side. I don't intend to upgrade to Windows XP (and fortunately, when the time comes, I will hopefully be able to run Doom 3 inside KNOPPIX because of WINE; it would have worked, had I had the video card to run it) because of stability and security issues. Now, on to the error: when I try to run linuxxdoom on the console, (can't run it in the main GUI) it gives me the error:
linuxxdoom: can't find library 'libXt.so.3'
What gives?