editing /etc/sysconfig in yast

Has anyone tried to edit the /etc/sysconfig file using yast? My experience is that while it states that possible values are "any value", I cannot enter anything by way of the keyboard. If there is a drop down selection I can choose that or by right clicking the mouse I can select "clear" but am still unable to type anything. I will edit the file directly but I was just wondering, is this a bug, is it suppose to work like that or am I doing something wrong? Eddie