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http://docs.sun.com/source/816-5691-10/essearch.htm#25618
To map a URL, perform the following steps:
Open the Class Manager and select the server instance from the drop-down list.
Choose the Content Mgmt tab.
Click the Additional Document Directories link.
The web server displays the Additional Document Directories page.
(Optional) Add another directory by entering one of the following.
URL prefix.
For example: plans.
Absolute physical path of the directory you want the URL mapped to.
For example:
C:/iPlanet/Servers/docs/marketing/plans
Click OK.
Click Apply.
Edit one of the current additional directories listed by selecting one of the following:
Edit
Remove
If editing, select edit next to the listed directory you wish to change.
Enter a new prefix using ASCII format.
(Optional) Select a style in the Apply Style drop-down list if you want to apply a style to the directory:
For more information about styles, see Applying Configuration Styles.
Click OK to add the new document directory.
Click Apply.
Choose Apply Changes to hard start /restart your server.