Indexing addresses with query strings
Any web address, even those with query strings, can be indexed from the main page. For example:
The query string is the part of a web address which follows the question mark.
When the crawler visits a page and adds all of the links on that page to the pending list, by default it will include addresses with query strings. This behavior can be changed. Visit the Admin Page, choose General Settings, and look for setting Crawler: Follow Query Strings. If unchecked, the crawler will ignore links to other documents if the links contain a query string.
"Indexing addresses with query strings" http://www.xav.com/scripts/search/help/1060.html