While I open my site via Mozilla firefox, the edges of buttons is not smooth and well-rounded, I don't have this problem via IE10 or chrome, Please check the following screen-shot:
http://www.jomsocial.com/media/kunena/attachments/118027/bdbtn.jpg
What is wrong?
Regards
Maybe you need the -moz prefix, but I think that the latest Firefox version doesn't need this prefix. Take a look to this website
So your CSS rule should be like
border-radius:4px;
-moz-border-radius:4px;
-webkit-border-radius:4px;
Ps: sorry for my bad English :P