What's stopping you from spending 30 seconds installing mIRC 6.21, typing /ddeserver off and seeing if irc:// links stop working?

mIRC 6.21:


mIRC 6.31:


Originally Posted By: versions.txt
16/08/2007 - mIRC v6.3
29.Fixed irc:// links not working under Vista.

I think you'll still be an idiot, though. Oh well.