You can have an extra field in the database called flag. In after rowcolchange repl the flag with "Y" and in the column1.text1.gotfocus put this code :

if flag="Y"
thisform.grid1.column1.ReadOnly=.t.
else
thisform.grid1.column1.ReadOnly=.f.
endif

I'm sure there are better ways to go about this.
HTH
Shafid