[Q] dbimport locking mode

Hello Informixers, Is there any way to change locking mode used by "dbimport"? Dbimport locks table rows, and when it tries to alter big table - for example, to add foreign key constraint - operation fails with message "No more locks available". So I need "Lock Table ..." before altering table and "Unlock ..." after One method to make it - edit file <export_dir>/<database>.exp/<database>.sql by hands. Another - write advanced awk script to perform such editions. Can I set dbimport behaviour by command-line options or by some settings - but _once_ and forewer? Increasing number of locks in "onconfig" is not a solution because table always can contain more rows than this number. Any help would be appreciated Leonid