possible misinterpretation of king-side castle?

[Ray Kiddy]

Hello -

I am going to send you this transcript, with my mistakes left in. I  
am new to using this, so excuse my mistyping and not-so-good chess play.

The problem is in move 6, where it says I am doing an illegal move. I  
think it is saying that because I had done a king-side castle in move  
5 with "d1b1". This would be illegal, of course, as a king move. But  
it is a legal king-side castle move and I thought that this is how  
the move would be interpreted. But then when I try to take the knight  
with "c1c2", it says this is illegal. Does it not think the rook is  
at c1?

If I am correct in my guess, then "d1b1" was accepted as a legal  
move, but the rook was not moved with a "a1c1". There is no "castle"  
or "kcastle" command, no other way to castle, no?

So, where is the problem? I am running this on Mac OS X 10.4.11.

thanx - ray

% /usr/local/bin/gnuchess xboard
Chess
Adjusting HashSize to 1024 slots
d2d4
1. d2d4
1. ... d7d5
My move is: d7d5
b1b3
Illegal move: b1b3
b1c3
2. b1c3
2. ... g8f6
My move is: g8f6
g1f3
3. g1f3
3. ... b8c6
My move is: b8c6
c1f4
4. c1f4
4. ... c8f5
My move is: c8f5
d1b1
5. d1b1
5. ... c6b4
My move is: c6b4
a2a3
6. a2a3
6. ... b4c2
My move is: b4c2
c1c2
Illegal move: c1c2
q
Illegal move: q
quit
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% /usr/local/bin/gnuchess -v
GNU Chess 5.07
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