No matter security on table editing. When in transaction SE16N use the command &SAP_EDIT in the command field in SAP and off you go: edit table content directly.
See my other post on how to track change by people who edited tables with this method.
1) Go to transaction SE16N or alternatively use shortcut and type just ‘N’. Enter here the table that you wish to edit.
2) In the command field enter ‘&SAP_EDIT’ and press enter. The maintenance indicator in SE16N will switch on.
3) Narrow your search results by entering selection criteria and press F8 to run the report.
4) You can remove lines or just add/change data and press save.
Voila! You just hacked your way into the table structure and made some changes.
Update 05-Oct-2009: interesting comments made on this hack: blog on IT toolbox