I have noticed that in a paragraph with padding and margin set to 0, text is rendered slightly different in Firefox and Safari. To be more precise, in Firefox the text start at the very top of the paragraph, whereas in Safari there is a small space between the top of the paragraph and the text. It has nothing to do with text alignment though.
Have a look at the screenshot. The top window is Firefox and the bottom one is Safari.
Anyone have any ideas what causes this?

Thanks,
Bart