After updating to rubygems 1.2.0 I've noticed that my mongrels started returning the following colorful error on every XHR load, i.e. all AJAX requests fail but regular page loads are fine:

Mon Jun 23 23:39:15 -0400 2008: HTTP parse error, malformed request (127.0.0.1): #<Mongrel::HttpParserError: Invalid HTTP format, parsing fails.>

Given that rubygems was the last thing I updated, I figured I'd try reverting to the previous 1.1.1 release using the following steps:

• uninstall all versions of the rubygems-update gem that were installed:
  sudo gem uninstall rubygems-update
• install the v1.1.1 rubygems-update:
  sudo gem install --version '1.1.1' rubygems-update
• manually run the updater to ensure that the stable v1.1.1 release was active:
  sudo update_rubygems

A few minutes of churning away and... still no biscuit! ARGH!

More updates when I get this working.

UPDATE: This is a weird one. I was poking around working on an official bug report to the error when I noticed that my ~/.gemrc had a duplicate source entry for github. I removed the duplicate, restarted the mongrels and... it worked! Go figure.