Delete button becomes disabled

Hi
I have a master detail form in Oracle ebiz 11i in which i have set the delete allowed property on the master block as No and on the detail block as Yes. When i open the form in the application, the delete button in the menu remains disabled even when in move the cursor to the detail block. I have confirmed thorough examine that the detail block delete_allowed property is true. Does some body have a clue why this is happening ?

Also, what is the form event that gets fired when we click on the delete button in the menu in oracle apps ? I tried key-delrec but that did not work and pre_delete fires only when i try to save after deleting the record