The recent Cheetah announcement covering the next major version of Informix Dynamic Server had a reference to a new feature called "record-level locking". This resulted in some speculation since "row-level locking" has been part of IDS for many years.
This was meant to be Label-Based Access Control. LBAC supports access to database objects based on labels, leading to highly configurable security policies, providing significantly increased control over who can access data. As mentioned in the press release, LBAC is already supported in DB2.
Label Based Access Control