Hello,
So yes you can do it, BUT that's a manual process.
Meaning, while CMOD is stopped you need to change directly in CMOD the size of your field (table ARSAGFLD), change the segment table ALTER TABLE ALTER COLUMN...
Then, it would be ok.
Otherwise, there is no other ways. Except maybe export/import !! :-) but I'm sure you are not going to be a big fan of it!!
And of course, do a backup before, and TEST IT !!!!!!!
Cheers,
Alessandro