Adding a infoobject

Hi all,
i am having a Cube in BWproduction system which is already in use and now the client has come with a request to add one more infoobject to that already existing cube.
i already have the data in that if i want to add a infoobject in Dev and then transport that to the Prd will the data existing will be deleted.
and if i add this field to the Datasource will i have to reinitialize from first like delete the old req and then initialize...any options. plz


so even if i add this field in datasource also i don;t need to do the re init right..jus do the replication and carry on with my normal delta loads.
if yes then how this infoobject will be populated
and is this the same even if its a key figure and i am not worried about the past data
any specific steps if this datasource is from Logistics
like clearing the RSA7 and clearing the extraction queue
please i am very confused and worried as its going to be into production system
thanks and regards