[Question] Why sometimes the unmerged file doesn't contains any conflicts

Hi all,

Sometimes when I merge two branches, the unmerged files don't contain
any conflicts.
When I edit the file, I can't find any conflict information. Usually
all I have to do is manually "git add" them.

I do the merge with a clean workspace, all changes have been committed.
This doesn't happen all the time, usually the unmerged files contains
the correct conflict information inside.

Do you know what's going on here?
The version of my git is: 1.6.2.1

Thanks for your consideration.

Regards,
Johnny

-- 
we all have our crosses to bear