<div>

<span></span>

<span></span>

</div>

$('div').innerWrap("<p></p>");

#=>

<div>

<p>

<span></span>

<span></span>

</p>

</div>

jquery.js #=> ln 142

backwards compatibility for wrap

wrap: function(){

return outerWrap();

},

outerWrap: function() {

The elements to wrap the target around

var a = jQuery.clean(arguments);

Wrap each of the matched elements individually

return this.each(function(){

Clone the structure that we're using to wrap

var b = a[0].cloneNode(true);

Insert it before the element to be wrapped

this.parentNode.insertBefore( b, this );

Find the deepest point in the wrap structure

while ( b.firstChild )

b = b.firstChild;

Move the matched element to within the wrap structure

b.appendChild( this );

});

},

innerWrap: function() {

The elements to wrap the target around

var a = jQuery.clean(arguments);

Wrap each of the matched elements individually

return this.each(function(){

Clone the structure that we're using to wrap

var b = a[0].cloneNode(true);

// Insert it before the element to be wrapped

var c = $(this).children();

$(this).children().remove();

this.appendChild(b);

$(this).children().prepend(c);

});

},