Enhancement in VF01

Hello All,

I have a requirement in which I have to stop the user at the time of saving the document in VF01.

The requirement is : If the quantity is not initial but the value is initial then the document should not get saved.

I have implemented a badi for this but that badi is getting triggered at VF02.

I also searched the forums and got one user exit EXIT_SAPLV60B_008.

But when I create a project in cmod and give the enhancement name SDVFX008 the system gives me an error of "SAP enhancement SDVFX008 already belongs to project ICGBILL"

So does any one having idea of this?