Try with 5/16, or older verison of knoppix (3.1). I couldn't make 6/6 work with any thinkpad at all. 5/20 stucks just like your A21. I test on tp 600es and T30s, and so far 5/16 is the only recent one that works.
I have an A22m, it will boot up into Knoppix runlevel 2 no problem. But when booting normally, after X starts, it appears to timeout on the "loading services". The mouse works fine and will move around the screen, but then loading screen will just disappear. The CD-ROM drive light just stays solid after this and the screen is blank, but the mouse will move around. Has anyone else seen this behaviour, or know of a solution?
I have tried both V3.2-2003-05-03-EN and V3.2-2003-06-06-EN.
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Try with 5/16, or older verison of knoppix (3.1). I couldn't make 6/6 work with any thinkpad at all. 5/20 stucks just like your A21. I test on tp 600es and T30s, and so far 5/16 is the only recent one that works.

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