A question about the QTopia addressbook and datebook apps (as delivered, out of the shrinkwrap, on a Zaurus 5600).

Records in the addressbook and the datebook are tagged with a unique ID field (for synchronization purposes, I presume) that takes the form (at least in XML) of a signed, negative 10-digit number.

Does anyone have any idea how this is generated when the record is created? Is it simply a uniqure random number? Or uniquely hashed somehow from the date and time or something??