DnD operation change feature does not work with 64bit big endian CPU

Following operation does not work with 64bit big endian CPU.
Test instruction is as follows:
1. Run Notepad demo package
2. Type "abc" on JTextArea component
3. Select "abc" and drag this text by mouse
4. Press Ctrl key to change operation.
  Mouse cursor should be changed from Move operation to Copy operation
5. Release Ctrl key
  Mouse cursor should be changed from Copy operation to Move operation
But step 5 does not work on 64bit big endian CPU, like Linux s390x and AIX.
Sometimes, step 4 may not work properly