Line Spacing NOT working, but other P stuff does…

I am designing my own skin for WordPress, and I can not for the life of me get the line-spacing in my paragraphs to be anything other than default.

I have tried line-spacing, margin top and bottom – all don’t move a thing. The same CSS P tag does read color, indent, etc… It’s almost as if it won’t let me overwrite something.

Here’s the code I’ve been using to test with:

p {
line-height:50px;
color:#3F0;
}

No matter what I set line-height to, or what measurement I use, I get ZERO changes in my spacing. But it does re-color my text.

I am using Firefox 3, if that matters.

Thanks!