For me, the 3/7 release had the missing APN and related MMS issues. I was also on one of the builds between 3/3 and 3/7 at some point (don't remember which), and I don't think I sent any MMS on those days, thus I'm not sure what the status was on those builds. I tried a clean flash and still had the issues right away, before installing anything again. I made sure I was on the latest radio, flashed back to stock to test, and MMS was still working on Sense. I clean flashed 3/7 again and it still had the issue. I saw that there were a number of APN and MMS related changes listed in the change log for 3/4, so I went back to 3/3 (which was also the oldest nightly on the servers at that time). 3/3 worked fine for me -- MMS worked right away after the clean flash.
I skimmed some of the changes that reference MMS and APN since 3/3, but nothing jumped out at me as being obviously the cause. But something in between 3/3 and 3/7 appears to be the issue.
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