The "bug" reports that flock is not entirely cross-platform (it's emulated decently on most systems which don't natively support flock but do support advisory locking). That simply means the target system needs to support flock (advisory locks). The report suggests a File::Lock module which doesn't exist (perhaps a good idea).

AgentM Systems nor Nasca Enterprises nor Bone::Easy nor Macperl is responsible for the comments made by AgentM. Remember, you can build any logical system with NOR.