In the 1.18 version of the Second Life viewer, the colour of the text from objects that use 'Owner Say', i.e. they only 'chat' to their owners, will become purple, and possibly unreadable.
This 1-minute video shows how to change this colour back to how it was before 1.18.
http://www.youtube.com/watch?v=kHHnzzvSfao
My other video tutorials can be found on youtube at
http://uk.youtube.com/profile?user=cgaa1395
Oh, and these videos can also be downloaded, see my blog at
http://benjakepler.wordpress.com/
Benja