text and img inside button

[Hengki Widjaja]

I have the following code:

<button><img src="files/img/save.gif">  Save</button>

1. How can I make the save.gif auto-size based on button's size ?
2. How to make the img vertically center?
3. how to make the "Save" caption vertically center? text-align, line-height, vertical-align didn't work

thanks.