Anyone know what a "d-line" on freenode.net means?

[Jason Dillon]

As of last night I keep getting this message when connecting to  
freenode.net:

<snip>
[20:31:23] Connecting to irc.freenode.net on port 6667
[20:31:24] *** You have been D-lined

[20:31:25] An error occurred (Operation could not be completed.  
Connection reset by peer)

[20:31:25] Disconnected

</snip>

I've no idea why... :-(

--jason