Example:

$cache = new Cache($cacheStorage,'namespace');
$cache->clean(array(Cache::ALL=>true));

result: whole cache was deleted

expected: only part of cache in "namespace" was deleted

Same issue has already few thread on forum [CZ]:
http://forum.nette.org/cs/7305-cache-clean-nemaze-len-svoj-namespace
http://forum.nette.org/cs/2309-cache-clean-jak-smazat-vsechny-data-v-urcite-namespace
http://forum.nette.org/cs/3145-nette-caching-cache-clean-mazat-pouze-namespace