Thank you for taking the time to report this bug and helping to make Ubuntu better. I'm in Dominican Republic, using natty, but the option is there (but in the fact, it doesn't work as said in the bug https://bugs.launchpad.net/bugs/754571 . Please upgrade to the most recent version and let us know if you are still having this issue. Thanks in advance.
** Changed in: langpack-locales (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/593436 Title: 12-hour clock not available in Latin Spanish locale -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs