Thank you so much for your help, I installed it and ir works perfectly!

Ahem... I don't want to be a party pooper after the big hurray, but did you try to click on "log out" on your 40 sites ? ;-)

Not a big issue, since I know very few people who actually log out, but I have sometimes very demanding clients and I'm sure that day will come with an email asking "my site has a broken link, thank you for fixing this".

I am clueless on how to fix this one...besides removing the log out link haha!