Foren / Cotonti / Skins / Skins for Siena

In header to address a picture from img in the theme directory you can use {PHP.theme}
eg: <img src="themes/{PHP.theme}/img/h2.jpg" width="385" height="103">

This does not work in index.tpl nor footer.tpl
Other tpl's not tested.
How can I address a picture in the img directory without using the real theme name in the link.