I'm quite possibly being a moron, but I've tried miraclemaker's code above several times now, and get a fatal error every time. Are there some parameters for where this should go that I'm missing?
Background: I'm trying desperately to mobilize a theme from Elegant Themes using their theme/plugin Handheld. The problem is that shortcodes on the main site are removed in the mobile version, which also removes the content inside them. I made a change to handheld.php which made the content visible, but now it's wrapped in visible shortcode text, which I need to get rid of.
I tried the above code, edited to reference two of Elegant Themes' shortcodes ([dropcap] and [one_third]), but both times the plugin was deactivated with a fatal error.
function my_shortcode_handler( $atts, $content=null, $code="" )
//override the 'dropcap' shortcode
add_shortcode( 'dropcap', 'my_shortcode_handler' );
Any idea what I'm doing wrong?