Changeset viewer intraline changes wrong

Viewing http://bitbucket.org/effbot/pil-2009-raclette/changeset/0fefd3a7cfb8/ the sub-hunk highlighting isn't working quite right. Lines 73-75 just have s/1/-1/ done do them, so those should be the only intraline changes marked up in that hunk. Instead it shows line 75 being edited to line 73, which is strange.

Screenshot attached.