cset macro fails to find changeset (BB-786)

eg: in http://bitbucket.org/normanr/rtirishrail/issue/2/store-a-list-of-favourite-stations

{{{
→ <<cset 5c589b79ac13>>
}}}

renders as:

→ Wiki macro error: Changeset 5c589b79ac13 not found.

and not:

→ [[http://bitbucket.org/normanr/rtirishrail/changeset/5c589b79ac13/|r6:5c589b79ac13]]