Hi Basil,
It seems you are implementing SAP for ECC & EWM as well as,if this is the case use old material number filed in basic data of material master to recognize the new materials in the ECC.
when you are distributing the materials in to EWM through CIF activity, try to map the old materials in to EWM products also..
for this , we can use the free attribute fields in the table '/SAPAPO/MATKEY' in EWM. those fields are 'ATT01' to 'ATT05'.
for mapping the old material numbers to EWM products,use the function module
'/SAPAPO/CIF_PROD_INBOUND' .
for picking through RF in EWM, amend the respective logical transaction to validate the free attribute field ( to check the old material number ) through verification controls.
This is an idea to compare the old materials with new materials.Any how check with your technical team to analyse in this way...
BR
C K REDDY