IIRC it was 2.01.17...
I was actually looking for a Messenger replacement back then... I thought Plus! was a new client of its own (it was just released)... When I installed it, it was a major bummer at first; it needed MSN Messenger to work... I thought, what the heck let's try it... I didn't regret it
I kept MSN Messenger because of Plus!, now I can't live without... (so to speak
)...
The reason why I tried it out, even if it wasn't what I was looking for, was that it was free and it felt and looked very professional and promosing. (never came across such a free quality thing since I first discover mIRC, back in the early 90's.)
/ 
