What about security mechanisms when using the NDEF operations provided by JSR 257? Is it possible e.g. to lock one specific record or similiar? I'm working at a project where the content of a tag is dynamic and should be changed by different user groups equipped with different access rights.

The Nokia API Extensions provide e.g. methods to specify keys for single MIFARE blocks but how to use these methods in combination with the methods for writing and reading NDEF messages?

Thanks for any hints,