THe cable broke on the inside and I can't figure out how to take off the end that hooks onto the lawn mower, because it's a weird squared off round connector that seems to require some special tool to take it off or something

Here is a pic of something kind of similar although it doesn't have the rounded end I mentioned
http://www.stens.com/images/catalog/290/290-102C.jpg

Anyone have an idea what I'm talking about and how to fix it, its getting warm already in TX and I hate having to get my lawnmower fixed every year it seems. I'd like to fix it myself.

Forgot how exactly, it's a ball end? http://www.murray.com/products/combined_search.asp?search=Model&type=OM
See if you can get the owners manual, its supposed to show you exactly, I'd have to be looking at it to tell you for sure.