Can't be done, currently it is:
* It's either another icon, and no password protection (Boss protection), or...
* Messenger icon, but with the choice of password protecting (lock protection)... (btw: many people don't know that you don't HAVE to set a password for the lock-feature
)
Another difference is the choice of statusses: with Messenger lock you can choose between fewer statusses (why? appart from the "online"-status (and even then there might be people to use it), I don't know)...)
[Suggestion to Patchou]
IMHO, the two features can easly be made into 1 feature as IMHO it seems a bit useless to have two of the almost exactly features....
So my suggestion to Patchou would be: make it into 1 feature:
* 3(or more?) different protection-scheme's (like in Boss protection)
* per scheme: ability to choose an icon (like in Boss protection)
* per scheme: ability to choose between all the statusses available, and also "no change" (like in Boss protection)
* per scheme: ability to set a hiding/come back message (like in Boss protection)
* per scheme: ability to close all the windows (like in Messenger Lock/Boss protection)
* per scheme: ability to set a password (like in Messenger Lock)
Like this, you have the exact same choices, but all is done by 1 feature and not two extremely similar ones and make it even more user-friendly
...