shows how to get the correct UTC time with no offset out of a Wordpress post

wordpress_utc_time.php

<? php

/*
	WORDPRESS: Howto get the UTC time of a post without an offset

	source: http://codex.wordpress.org/Template_Tags/get_post_time

	- the 'c' formats datetime string in ISO8601
	- the 'true' advises Wordpress to calculate the UTC/GMT 
	  instead of the timezone defined in Wordpress

	from wp-includes/general-template.php:
	function get_post_time( $d = 'U', $gmt = false, $post = null, $translate = false )

	note: other functions rely on this one, like 'the_time' and 'get_the_time', 
 */

get_post_time('c', true)

get_post_modified_time('c', true)

?>

And this is how should looks the time html5 tag:

<time itemprop="dateCreated" datetime="<?php echo get_post_time('c', true);?>"><?php the_date(); ?></time>

of course for any timezone :)