I found that if I get a text message on my Google number and I don't read it right away, after a while I will get a message waiting light and stutter tone on my phone. I like this, however, but I wonder if this is something everyone else is getting. I then go to my PC and read and delete the message but then have to call mailbox from my phone for light to go out. Maybe if I wait long enough the light will go out on it's own after I read the text message.
Update: Certain conditions have to be met in my situation for the message light to be blinking: I have to be signed out of GV, computer in hibernation (or so I think) and block anonymous calls enabled in Obi (*77) BEFORE someone sends me a text message. Later, when I see the light blinking I turn on computer, sign in to GV, mark message as read, go to my phone and call mailbox, then hang up. Light stops blinking in less than 15 seconds. Whew!