Guess recently eveyone is sicked of all those spam bots, and their junk notices. Try the following,

1. Download this little addon from
2. Copy to your mirc folder
3. Type /load -rs notice.mrc in your mirc tool to load the addon.

DONE! All the junk notices will be consolidated into another window, so none of your convos will be affected.

Give it a try, let me know the outcome.