advanced search on activity type produces incorrect pager results and more records than should be returned

The problem happens if you do an advanced search, expand the activities section, and search on one or more activity types.

The pager reports over 360,000 results (on a database with 13,000 contacts). Also, it only displays 3 results on the first screen, despite having 50 as the number of results to display per page. I'm expecting one result per contact with an activity of the types I specified and 50 results per page.

I've tracked the problem down to the code in Contact/BAO/Query.php.

The query function seems to set $this->_useDistinct = false if $this->_distinctComponentClause is not set.

As a result, the search does not use DISTINCT and we get duplicate contacts because a contact could be coded to more than one activity of a given activity type.

I'm not sure how to fix it.