The Enterprise COBOL compiler now uses the Language Environment STACK storage work area for several functions, including UPPER-CASE, LOWER-CASE, and NATIONAL-OF. If the STACK is allocated below the 16-MB line and a large DSA (Dynamic Save Area) is needed, an insufficient storage error might occur.
To see the amount of storage that is required, compile your program with the compiler options MAP and LIST. Look for this line under the DSA MEMORY MAP: DSA WILL BE ALLOCATED FOR nnnnnnnn BYTES
You might need to reduce the amount of storage required or change to STACK=(...ANYWHERE..) to use storage above the line.