"gem install watir" to the latest.

New Features

• Multiple attributes can now be specified for these elements:
  li, ul, map, area, h1, h2, h3, h4, h5, h6. (This was claimed to work earlier,
  but never did.)
  http://jira.openqa.org/browse/WTR-196

Bug Fixes

• Statements such at ie.table().row() now work (no longer private).
  http://jira.openqa.org/browse/WTR-117
• Fixed bug with images method when used with anything but ie. (Paul Rogers)
  E.g. ie.div().images. http://jira.openqa.org/browse/WTR-211
• Fixed intermittent bug with ie.file_field().set. (Tomislav Car)
  http://jira.openqa.org/browse/WTR-210
• When installing Watir 1.5.4 you could get extra, confusing
  questions. This shouldn't happen anymore.
  http://jira.openqa.org/browse/WTR-209
• Improved error message when element is not found using multiple attributes.
  http://jira.openqa.org/browse/WTR-181
• Made examples and unit tests somewhat better examples: removed unnecessary
  "include Watir" statements; started using "browser" instead of "$ie"; use
  new methods 'goto_page' and 'uses_page' (this last improves performance of
  unit tests).
  http://jira.openqa.org/browse/WTR-159
• Moved brittle unit test that was causing cascading failures; renamed another
  that was causing a namespace collision.
  http://jira.openqa.org/browse/WTR-92

To install this:

"gem update --system"
"gem install watir"

Installer Fix

This update fixes an installer problem in Watir 1.5.5 that affected some users.
If you installed 1.5.5 without error, there is no reason to get this update.