Wrong diff in changeset page

hg repo: http://www.bitbucket.org/ctrochalakis/tx-submissions/overview/\\
rev: 3a3888e7ab1d

The diff calculated in changeset view is wrong (file transifex/controllers.py), http://www.bitbucket.org/ctrochalakis/tx-submissions/changeset/3a3888e7ab1d/

The correct one is here:
http://www.bitbucket.org/ctrochalakis/tx-submissions/diff/transifex/controllers.py?diff2=3a3888e7ab1d&diff1=2dc94b06be52

I don't know if it's relevant but the last time this file was modified was in a merge commit. (2dc94b06be52)