User Exit that will allow the SAP program to create DN, but not create IDO

Hi all,

The requirement is when we select 1 PO in VL10g transaction and click the u201CBackgroundu201D button, the user exit will allow the SAP program to create Delivery Number, but not create IDOC for the Delivery Number to send it to warehouse system. Also the created Delivery Number must be in changeable mode in ECC system .I need to find any exit to make the DN table field LIKP-VLSTK not to be u201CBu201D (distributed). The B will make DN not changeable in ECC system which is hard coded value in standard program. so the DN should be changeable.

Please suggest me the User Exit name which serves my purpose.

Thanks in advance

Latha.