Added new lean config option com.openexchange.spamhandler.name that specifies the name of the spam handler to use for the primary mail account. The special name NoSpamHandler explicitly sets no spam handler. If such a setting is not specified, the spam handler as configured through the mail bundle is used (as it was before); e.g. com.openexchange.imap.spamHandler in file 'imap.properties'.

That option is reloadable as well as config-cascade aware.