We've done our fair share of troubleshooting with the Tanjay phones lately as we have internally and at client sites various beta phones with the original firmware, R1 firmware and R2 firmware versions. I wanted to write a quick entry about how to update these phones.
First off, read this article to get an understanding of how the process works: http://blogs.technet.com/ucspotting/archive/2009/03/11/troubleshooting-ocs-2007-r2-device-update-service-for-communicator-phone-edition.aspx
Second, if you have a SIP URI and SMTP domain which is different than the fqdn of the domain (i.e. contoso.com for SMTP/SIP and contoso.local for AD) and you don't have WINS deployed then you will likely have an issue with the entire process.
You MUST MUST MUST deploy a WINS server and point your Domain Controller at the server so it registers the domain in WINS. You also need to add a static entry called "ucupdates" which points to your R1 update server.
If you're updating an R1 phone in an R2 pool and you have the above mentioned issue with the domain fqdn being different from your SIP URI domain, then add a static WINS entry called "ucupdates-r2" which points to your R2 front-end server.
If you're updating a beta firmware phone this MUST be done in an R1 environment first before logging into R2.
We worked with Microsoft extensively on this issue troubleshooting it by capturing Wireshark traces through the second network port on the phone. You can see the requests for WINS entries going out and if you don't have WINS running properly in your environment, this won't work at all.
NOTE: You may need to perform a hard reset on the phone once you update the beta firmware to R1. If you sign into an R2 pool an expect the phone to update and it doesn't, reset the phone and wait 5 minutes.
Hope this helps!