Comment 3 for bug 460144

As detailed in bug #460964, network manager can merge asynchronous notifications when a new one should supercede an old one by giving them the same title. This is in keeping with then notify-osd guidelines:

https://wiki.ubuntu.com/NotifyOSD#Merging%20notifications

Assuming notify-osd is implemented according to the spec, it should be a relatively easy fix. Doesn't really affect notify-osd.