Pagination of course was something that I was so stupid not to test...
But actually both FF and IE should behave the same - means refresh of the page if you are not on the page where the comment should be shown.
To change this go to client.js line 207 and change it from
window.location = JOSC_linkToContent + sep + 'comment_id=' + id + '#josc' + id;
to
window.location = JOSC_linkToContent + '#josc' + id;
You can also comment the whole line... We've had the same problem with you in the past and this is going to change for real! The whole process of adding messages going to become nicer
I've tested 4.1.8 on IE8 and I didn't have any problems and you also should not have. The js code that we've added is only executed if the js function is not existing, but it is in IE8 - so it should behave as usual...
Daniel
P.S. When you make the changes don't forget to clear the cache!