[Thank The Cheese]

A client of mine is using Drupal for a website. Suddenly, Â characters are popping up wherever an apostrophe appears. I've seen this before when cutting and pasting into a text editor from a rich text format, but why has Drupal suddenly begun doing this? Even if contributors are cutting and pasting from Word, it doesn't explain why it has been fine for the last 6 months. :/

Is there an easy to to remove these buggers? And is there a way to prevent them showing up in the future? I wonder if someone has flicked on a setting somewhere that is causing them.