git-rev-list bug?

Sorry if this was previously discussed. I ran git-rev-list on a linear
graph and tried to filter the results by a file name:

  git rev-list since.. path/to/file

but it always shows the child commit of "since" even if it didn't
touch the file. The same behaviour is for git-log (since it uses
git-rev-list) but git-whatchanged seems to be fine.

Is this the intended behaviour? The "stg patches" command based on
git-rev-list used to work fine a few weeks ago but now it is always
reporting the bottom patch in the stack as modifying a given file.

Thanks.

--
Catalin