Accessing/Filtering by Custom Result Fields in Reports

Hi

I've added a new 'Custom Result Field' called 'Build Type'. Which is a dropdown, providing the 2 options (DEV, RC). DEV = Development build, RC = Release Candidate.

I'd like to be able to filter on this field in a report, so I can separate out the test results on DEV builds and RC builds.

I can't see a way (using a built in report) to select a custom result field.

Is this possible?

Thanks
James.