when msgplus is installed, it should register a protocol (like msgplusunlock:// or something) that launches mptools.exe with some parameter that makes it show a balloon in the notification area explaining how to unlock messenger. this would make it easier to help people on the forums and on IRC who accidentally locked their messenger without realizing it, as they'd just be able to click a link and then be directed to the icon they need to click -- e.g.:
newb: how do i unlock my messenger??/
me: click
here