Justin,

If PO is integrated with IM and the PO type isn't material requisition, the lookup is CI_ItemAllExt.  This is how I figured it out without looking at the code:

In PO entry lines tab, launch the ALE, customize the ALE in some way (eg. create a view).

Go to data file display and maintenance, open SY1Q01.SOA in the MAS90\SOA folder.

Click the lookup button next to the Key field on the bottom of the screen.

Scroll to the bottom of the list and look for a record that has the company code + user code and a "A" in the key.  The last part of the key is the lookup name.

This item code lookup may be used in many places.  You will customize it for all those places, not just PO entry.

Justin,

If PO is integrated with IM and the PO type isn't material requisition, the lookup is CI_ItemAllExt.  This is how I figured it out without looking at the code:

In PO entry lines tab, launch the ALE, customize the ALE in some way (eg. create a view).

Go to data file display and maintenance, open SY1Q01.SOA in the MAS90\SOA folder.

Click the lookup button next to the Key field on the bottom of the screen.

Scroll to the bottom of the list and look for a record that has the company code + user code and a "A" in the key.  The last part of the key is the lookup name.

This item code lookup may be used in many places.  You will customize it for all those places, not just PO entry.