Conversion Issue - MF OC 4.2 to Server Express 4.0

Given the following procedure division source code:

display "Hello"
at line 01 col 01
end-display

display "There"
at line +1 col 01
end-display


I get the following complier error:


12       at line +1 col 01
*  65-S******************
**    Unsigned integer required
cob64: error(s) in compilation: testme.cbl


This same code compiles fine under OC 4.2. Was this a "feature" on 4.2
that was really a bug, because I cannot find any supporting docs.

Had anyone else seen this behavior?

Thanks in advance.

Chris