Create a html_header template only for articles (for example call it html_header_article.tpl and put it in your article/default.tp instead of html_header.tpl)
In html_header_article.tpl before </head> add the following code:
Code:
<script language="JavaScript" type="text/javascript">
if (navigator.userAgent.match(/Android/i) ||
navigator.userAgent.match(/webOS/i) ||
navigator.userAgent.match(/iPhone/i) ||
navigator.userAgent.match(/iPod/i) ||
navigator.userAgent.match(/BlackBerry/) ||
navigator.userAgent.match(/Windows Phone/i) ||
navigator.userAgent.match(/ZuneWP7/i)
) {
window.location = 'http://yoursite.com/mobile/<vte:value select="{article.get_href}" />';
}
</script>
Ofcource you can add or remove userAgents.
Also replace yousite.com with your actual site url
I hope to help you