Translations:FAQ/146/en

Solution
Two options:
 * Use a KLINE or GLINE instead, which can be placed on a hostmask
 * Place the ban on the IP of the user (eg: *@194.92.91.90), you can get this by /WHOIS'ing the user (the 'connecting from' line). If the user already left then you could use your '/dns [host]' client command, although that's a tad less safe[1].