Sometime recently, support for non-roman Characters stopped working. I'm not sure yet if this is a problem on Phoenix's end or Livejournal's. I imagine it's on Livejournals as we've had Unicode support working for the last seven years or so. I'm looking into the problem, and will let you know more as soon as I do.
If you're using a version prior to v.1.10.1, Phoenix will hang and crash if you try to make a post with non-roman characters. If you're using v.1.10.1 you'll get a message that Livejournal has generated an Internal Server Error 500.
Big thanks to
everyueveryme for figuring out it was an issue with Unicode!