Thank you for your response. I have followed your instructions, and they work. While this is a step in the right direction, it's still not correct.
I would direct you to the Verizon Messages FAQ at http://support.verizonwireless.com/support/faqs/FeaturesandOptionalServices/verizon-messages.html. Bullet 21 reads as follows:
-- Does Verizon Messages include an address book that’s different from my phone’s address book?
-- No, Verizon Messages uses your phone’s address book and contact list. It doesn’t generate a unique address book.
For me to have to add a contact name to each conversation in the web application is in direct contrast to what's written in bullet 21. In addition, there is no synchronization. For instance, let's say I have a contact in my phone named "John Doe". In the web application, I went to the conversation I had with John and added his name as "Bill Smith". The web application now works as it's supposed to, as long as I refer to him as Bill Smith. If I type "John Doe", no contact is recognized. This means that the Integrated Messaging web app is indeed keeping a separate, non-synchronized contact list, exactly what it's NOT supposed to do. This clearly takes away from the "seamless" experience that Verizon Integrated Messaging is marketed as supporting.
Further, there appears to be another technical glitch. Each time I add a name to a conversation (as per your instructions), I receive an unexpected text message on my phone from 6200, with a cryptic message, something like this: