The server is 1.3.2 because A) im waiting for importantplugins to update, i.e. WordEdit, LogBlock, HeroChat, etc. and I am halfway across the globe currently. I will be back on the server next saturday morning, and I will upgrade the server as long as the plugins are updated. As for the internal server error, the cause of that seems to have been from conflicting plugins, and after scraping the server of most plugins, and then restarting the server I believe the issue is solved. If you still can not get in, I will need all details of what your doing and what youve tried. My suggestion is restarting your computer, removing all of your mods and trying with a NEW minecraft.jar file, and the solution which has worked for everyone else- just logging back in after 2-3 minutes. After you try all of it, if your not on the server I will be very surprised. Also, make sure that you downgrade to 1.3.2. Use MCNostalgia. They are the best, in my opinion, for downgrading Minecraft. Sorry for typos, im on my iPad and typing is highly annoying.