Sorry if this has been brought up, a search didn't reveal this tidbit. Poking around for the latest desktop manager, I found that RIM is now offering a download for the 8320 (and 8220) devices themselves, it's not carrier specific:
Software For BlackBerry® Curve (TM) 8320 smartphone
BlackBerry Handheld Software v188.8.131.528 (Multilanguage)
Package Version: 184.108.40.2068
* Applications: 220.127.116.11
* Software Platform: 18.104.22.168
* File name: 8320M_PBr4.2.2_rel338_PL22.214.171.124_A126.96.36.199_RIM.exe
* File size: 99.73MB
Go to this link: https://www.blackberry.com/Downloads...93E4F3BB068C22
...then choose the 8320 option near the lower part of the list (on my browser, you have to scroll down to actually see this option).
For those of us still choosing to stick to 188.8.131.52 until 4.5 has smoothed out a little, this is a nice option to get a generic release and not have to worry about vendor.xml (at least, I think - still downloading it myself). A nice little download to tuck away for a rainy day.