i guess you don't have the constants for the mode parameter defined. that's why it fails using strict subs. no strict "subs" wont help either, it just doesn't complain that the functions O_CREATE etc aren't defined. so just
use Fcntl;
or
use Fcntl qw(:DEFAULT :flock);
to pull in the flags your system supports.

hope to help, cheers
snowcrash //////