But here is my naive approach: Assumed you have a memcache object in PHP 5 with some servers registered using addServer Method, the following can be used:

	    $list = array();
	    $allSlabs = $memcache->getExtendedStats('slabs');
	    $items = $memcache->getExtendedStats('items');
	    foreach($allSlabs as $server => $slabs) {
    	    foreach($slabs AS $slabId => $slabMeta) {
    	        $cdump = $memcache->getExtendedStats('cachedump',(int)$slabId);
    	        foreach($cdump AS $server => $entries) {
    	            if($entries) {
        	            foreach($entries AS $eName => $eData) {
        	                $list[$eName] = array(
        	                     'key' => $eName,
        	                     'server' => $server,
        	                     'slabId' => $slabId,
        	                     'detail' => $eData,
        	                     'age' => $items[$server]['items'][$slabId]['age'],
        	                     );
        	            }
    	            }
    	        }
    	    }
	    }
	    ksort($list);

I then added a very simple HTML Table output to list the result array and found out some interesting details about my application that i dont want to share here

It worked for me but it could be that for bigger Memcache Clusters (mine has only 10 servers) or big content tables this will not return the complete content. More to come...