Is it permissible for a woman to dye the hair upon her head with black dye?

Fatwa, posted 4.22.2010, from Saudi Arabia, in:
Religious Authority: 
Abdul-Aziz ibn Baaz
Fatwa Question or Essay Title: 
Is it permissible for a woman to dye the hair upon her head with black dye?
Websites and Institutions: 
Fatwa Islam, Internet Catalogue

It is not permissible for a woman or other than her to colour their hair with black dye, because of the statement of the Messenger sallAllaahu ‘alayhi wa sallam: ”Change this colour, and stay away from the black (colour).” [Reported by Muslim in his Saheeh.]

As for changing (the hair colour) with other than black, then no problem, or (changing it) with henna or mixed al-Katam, ( ‘al-Katam’ is a plant that gives a dark colour, from the myrtle family) so there is no problem with this if the colour changes to other than black, or between black and red.