Solution : https://service.sap.com/sap/support/notes/930742 (SAP Service marketplace login required)
Summary :
The ABAP editor in SAP GUI 6.40 lacks support for the AB4 control due to backend programming limitations. It is recommended to import the Support Package for Basis Releases 6.40 and 6.20 to enable this functionality. No advance correction through correction instructions is available.
Key words :
terms ab4 control reason, ab4 control contained, relevant support package, support package, program support, abap editor, basis release 6, advance correction, correction instructions, prerequisites
Related Notes :
891549 | FAQ of the new ABAP editor as part of SAP GUI |
843289 | ABAP Editor as part of SAP GUI 6.40 |