CA IDMS Tuesday Tip by Edward Gorga, Principal Support Engineer for March 4, 2014.
The UT003010 indicates that all areas involved in the UNLOAD are not defined to the segment coded on the utility's input parameter.
According to the Utilities Guide section The Unload/Reload SEGMENT
The SEGMENT used in the unload and reload operation must include:
The area(s) being unloaded.
All areas with physical connections to the area(s) being unloaded.
Areas containing indexes on records or tables being unloaded.
Areas with set connections to areas being unloaded.
Areas containing tables related through a constraint to tables being unloaded.
There is no way to get around this requirement with Unload/Reload.
But, you can with the REORG utility. The REORG works on the DBNAME level, so you would need to define all segments to the same DBNAME.
The DBNAME should be the same name as the segment being REORGed. See the Utilities manua section Special Database Considerations