New one on me but tested and true. I held the f key for about
40 seconds and it sent it to the channel. Did the same in a
query window. This should be reported as a bug.

~ Edit ~

Give this code to your sleepy friend and have them paste
it in the remotes section of their mIRC script editor.

Code:
ctcp *:WAKEUP!:?:splay wakeup.mp3


Then have them download wakeup.mp3 and place it in their mIRC folder.

Then when they fall asleep type /ctcp nick wakeup!


wink