After the release of the 1.6.4 version from minecraft ,I observed that this program did not work for all the snapshot wich are after this version (1.6.4) but the version 1.6.4 still work :
So,the snapshot : 13w38a,13w38b,13w38c,13w39a,13w39b,13w40a,
13w40b,13w41a,13w41b crash when the title "Mojang" appear. I think it's the game wich freeze ; You can see a screenshot of the minecraft launcher at the bottom.I've already tried to wait (2 hours) but the development console still locked like that :
Client> OpenAL initialized
Client>
I am using Ubuntu 12.4, I've already tried to delete this programm and install them.But it won't work.

sorry for my English,I really hope that you will solve this problem