How to ignore Eclipse task tags in certain directories?

In Eclipse (HELIOS) there is an option to scan all source code and search for task tags such as "TODO", "FIXME" etc.
The result is then shown in a fine list.
One can access this list by: Windows->Show View->Tasks.
However, it also scans resources directory and libraries, whose task tags are not of my interest.
How can I filter Task Tags searching by directory exclusion filter?
10x