ReadOnly field saved with NULL value

On CRM opportunity form view, i added readonly="1" for probability field. When i saved, whatever the value of my probability, it's stored with NULL value. Is it a bug on OpenERP ?

 

I think its a bug in openerp. I have created a patch for that. In the openerp addons, web module, goto static/src/js/view_form.js.

Index: view_form.js
===================================================================
--- openerp/addons/web/static/src/js/view_form.js   
+++ openerp/addons/web/static/src/js/view_form.js   
@@ -833,11 +833,9 @@
                     // Special case 'id' field, do not save this field
                     // on 'create' : save all non readonly fields
                     // on 'edit' : save non readonly modified fields
-                    if (!f.get("readonly")) {
-                        values[f.name] = f.get_value();
-                    } else {
-                        readonly_values[f.name] = f.get_value();
-                    }
+                   values[f.name] = f.get_value();
+                    if (f.get("readonly"))
+                       readonly_values[f.name] = f.get_value();
                 }
             }
             if (form_invalid) {