[IRCServices Coding] Services 5.0a22 Segfault on unlink

[Mark Hetherington]

What appears to have happened is a user has nick1 and nick2 registered amnd 
desired to link them. User tried to drop nick2 as nick2 but did not provide 
the correct password to do so. After some confusion, the user then tried to 
unlink nick2 as nick2 despite it not being linked to anything. 

nickserv/link: [Feb 23 13:16:16 2002] PANIC! buffer = :banshee PRIVMSG 
NickServ at services.ctcp.net :unlink banshee
Services terminating: Segmentation fault

I guess it could be as simple as "unlink self" causing the crash. 
Hopefully, that will be sufficient information to begin tracking down the 
bug, I will try to get a fully reproducible case later.

-- 
Mark.