What is your setting for sef-urls? And url configuration?
And do you use autogenerated canonical urls?
I am not able to simulate your version url with .html, but of course, it's not correct.
in e_meta.php you need to change 3rd parameter (more times) to false:
This is not problem if you use standard sef-urls.
But you are right, this is already solved during generating urls, so why to do double check.
Sorry for problems, but I didn't test it with .html version of url. How you get it this way?