(Rant Mode Enabled)
MIMOSA
is the proper name for Beta Crucis.
The offensive astronomical swear-word
Becrux 
is just a nasty American invention, who mostly cannot even see it as it is below their owm horizon!
Astronomical American Imperialism just gives me the screaming willies!
This article might help you know why?
http://homepage.mac.com/andjames/Page208.htm
(Sorry for the shouting, but sometimes it is necessary.)