Trixbox and call waiting
So I have one client who just migrated from using Trixbox (neé Asterisk@home) in a VMWare as his telephony platform (along with a bunch of Grandstream SIP phones) the newest version (2.2) natively on the machine. (They were experiencing the things you'd expect by running a timing-based application from within VMWare—bad sound quality, odd playback of audio files, etc.)
So we backed up the old data stores, installed Trixbox natively, and things went about as smoothly as you could expect.
One function that had never worked out of the box, for some reason, was call waiting: even though users would enter *70 to enable call waiting, for some reason the asterisk DB (an oldy moldy Berkeley DB database) wasn't taking the change.
The solution was to run the following from the asterisk console (asterisk -vr):
For each extension, execute the following command
database put CW <extension> ENABLED
...and that does the trick!