Comment 1 for bug 101285

This was rolled out in Silva 1.6. From the 1.6 changelog:

- index items now have an 'index title' attribute in addition to an
        'anchor name' attribute. The title is used for displaying in an
        indexer. The name is used for the anchor, and thus should be a valid
        anchor name. If no title is given, the index is considered a 'simple'
        anchor, and will not be found by Indexers.