JdbcStringBasedCacheStore preloads data using wrong keys (it shouldn't preload)

It appears that if I happen to configure a JdbcStringBasedCacheStore using preload=true then cache is preloaded with the values but using the keys in their String form - which is pointless.

An error should be thrown, like illegal configuration, or a warning logged at runtime while attempting to load from this implementation and ignoring the load request.
Also documentation is not pointing out this limitation.