Recommended use with WordPress 2.9.2

How to setup / use:
- Enable obopac plugin.
- Add 'Search OPAC Widget' to sidebar & set URL path to OpenBiblio directory, done.
- Search with keywords:
  * Space (eg. a b, a b c) results books which match least one keyword.
  * OR (eg. a OR b) results as same as space words.
  * AND (eg. a AND b) results books which match both sides keywords.
  * NOT (eg. NOT c) results any books which not match following keyword.
  * For complex keywords, search would be parse from left to right.
