I\'m attempting to re-install Ruby 1.9.3 with a patch that will allow me to use ruby-debug.
When following the instructions and running
rvm reinstall
If you're using brew, then the autoreconf utility is part of the autoconf package, so install it via:
brew install autoconf
If the problem persists, consider either reinstall or link it again. Use locate autoreconf to find out where it is.
Also check if /usr/local/bin/autoreconf exists (and is linked into the right place), and you've the /usr/local/bin path added in your /etc/paths file.