:hover pseudo class and spans

I was just working on a page that when hovering over an element it would change the background colour, the element in question was a span tag. The CSS I was using was

editable-element:hover
{
background-color:#EEEEEE;
border:1px solid black;
cursor:pointer;
}

which works fine and dandy in Safari 4...I noticed it did diddly squat in Firefox 3.5, the solution change it to

span.editable-element:hover
{
background-color:#EEEEEE;
border:1px solid black;
cursor:pointer;
}
It seems FF needs the element type when using :hover and alike.