function add_query_arg() {
        $ret = '';
        if ( is_array( func_get_arg(0) ) ) {
                if ( @func_num_args() < 2 || false === @func_get_arg( 1 ) )
                        if ( get_bloginfo('url') != '' )
                                $uri = get_bloginfo('url') . $_SERVER['REQUEST_URI'];
                        else
                                $uri = $_SERVER['REQUEST_URI'];
                else
                        $uri = @func_get_arg( 1 );
        } else {
                if ( @func_num_args() < 3 || false === @func_get_arg( 2 ) )
                        if ( get_bloginfo('url') != '' )
                                $uri = get_bloginfo('url') . $_SERVER['REQUEST_URI'];
                        else
                                $uri = $_SERVER['REQUEST_URI'];
                else
                        $uri = @func_get_arg( 2 );
        }

        if ( $frag = strstr( $uri, '#' ) )
                $uri = substr( $uri, 0, -strlen( $frag ) );
        else
                $frag = '';

        if ( preg_match( '|^https?://|i', $uri, $matches ) ) {
                $protocol = $matches[0];
                $uri = substr( $uri, strlen( $protocol ) );
        } else {
                $protocol = '';
        }

        if ( strpos( $uri, '?' ) !== false ) {
                $parts = explode( '?', $uri, 2 );
                if ( 1 == count( $parts ) ) {
                        $base = '?';
                        $query = $parts[0];
                } else {
                        $base = $parts[0] . '?';
                        $query = $parts[1];
                }
        } elseif ( !empty( $protocol ) || strpos( $uri, '=' ) === false ) {
                $base = $uri . '?';
                $query = '';
        } else {
                $base = '';
                $query = $uri;
        }

        wp_parse_str( $query, $qs );
        $qs = urlencode_deep( $qs ); // this re-URL-encodes things that were already in the query string
        if ( is_array( func_get_arg( 0 ) ) ) {
                $kayvees = func_get_arg( 0 );
                $qs = array_merge( $qs, $kayvees );
        } else {
                $qs[func_get_arg( 0 )] = func_get_arg( 1 );
        }

        foreach ( (array) $qs as $k => $v ) {
                if ( $v === false )
                        unset( $qs[$k] );
        }

        $homeurl = str_replace(( is_ssl() ? 'https://' : 'http://' ), '', get_bloginfo('url'));

        $ret = build_query( $qs );
        $ret = trim( $ret, '?' );
        $ret = preg_replace( '#=(&|$)#', '$1', $ret );
        $ret = $protocol . $base . $ret . $frag;
        $ret = rtrim( $ret, '?' );
        $ret = str_replace($_SERVER['HTTP_HOST'], $homeurl, $ret);
        return $ret;
}