isolating a div tag

[sfullman]

suppose I have captured a string of (hopefully valid) XHTML code. There is a div in there with an id of some value, i.e.:

<div id="somevalue">
.. other divs and etc. here - no real control over what is inside..
</div>

is there any NATIVE function in php which could find and return that tags outer HTML (i.e. the div wrapper as well as the inner content)? for example

get_tag($haystack, 'id', 'somevalue');

thanks

[NogDog]

How about the [man]DOM[/man] functions, e.g. DOMDocument::getElementById()?