private boolean isInCapsCache(String verAttribute) {
        return entityCapabilitiesMap.containsKey(verAttribute);
    }
Determines whether or not a particular 'ver' attribute is stored in the
{@link #entityCapabilitiesMap} cache.

@param verAttribute the 'ver' hash to check for.
@return true if the caps cache contains the 'ver' hash already, false if not.
xmppserver/src/main/java/org/jivesoftware/openfire/entitycaps/EntityCapabilitiesManager.java