Iit is dsme task to read/write the lock code in the CAL area.
Unfortunately, it is closed source "added value" (ha! negative value).
Fortunately, it has been opensourced in good part in frematle: http://repository.maemo.org/pool/fremantle/free/d/dsme/
Unfortunately, I can't find anywhere some header files (protocol.h, message.h...) referenced there.
But those seem to have been opensourced for meego, not the same but may be similar enough: http://meego.gitorious.org/meego-mid...r/include/dsme
And finally, it has been reverse engineered in powerlaunch. Look at powered/dsme.c ( https://garage.maemo.org/plugins/scm...ch&view=markup ), You could copy-paste the code from there.