I guess this is a bug with JoomlaComment.
I'm using J1.5 with JoomlaComment 3.26, and what happen it this.
If anyone add a comment, dosent show the comment, need a reload to show the comment.
If you want to test, this is the website:
http://www.ronildo.com.br/blog/
Can post any test there, later I will erase this tests, ok??
thanks.