external diff tool opens one file after another

I am using kdiff3 as my external diff tool using bzr diff --using kdiff3. The problem is that bazaar launches the external diff tool for each file that has changed. For example, say I have 17 files that changed, the external diff tool is launched 17 times for each changed file one after another, instead of launching the external diff tool a single time, presenting a list of files that have changed, which then can be selected to drill down on the differences within the selected file. There should be a way to allow external diff tools to handle the output of bzr diff command, similar the way qdiff does it. QDiff is nice, but I don't like that it shows ALL changed files in one single window, which can take a long time to show and makes it more difficult to find a particular file. Thanks a lot.