As always, WebOS community comes through!
Originally Posted by bluetiger512
I had the same problem: not being able to dial from the Bluetooth kit connected to the Pre3. This was with a Viseeo MBU-1000 kit (aftermarket add-on for Mercedes) in one vehicle and with OEM Chrysler/Dodge Uconnect radio in another. My phone is a Pre3, with AT&T version 2.2.4 firmware.
As advised, I changed International Dialing to ON.
For those who are not familiar with this, the selection is in Phone App, pull-down for Network Services. Make sure to close the menu and the app - changes do not have an effect before that step.
Now, I successfully dialed from the internal phone address-book in the ViseeO kit and from the pre-stored address book in the Chrysler Mopar kit. Case closed. Thanks!
By the way, this is obviously a bug in the Pre3; I did not have this setting set to "on" in either my Veer, nor in my Pre Plus.