I've reproduced this here and the behaviour does not seem correct/expected, to me. I've created ticket for the issue (RT-3481) and will forward it along.
Please note that it is almost certainly too late to fix this for the next release.
If posting files to this forum, you must archive the files to a ZIP, RAR or 7z file or they will not be uploaded.
Tracker Support (Europe)
Tracker Software Products Ltd.