Shopping cart item level approval through cost centre

Hi all,

I am new to SRM workflow, we are using SAP SRM 7.0 and We have configured shopping cart process oriented workflow using process schema 3C_SC_600_001. As of now it is working fine for two levels of header level approval. we need an another level of approval but by item wise cost centre. the approvers are the cost centre owners which are in R/3 not in SRM.

Please help me out how to configure,what to configure , how to fetch item cost centre and how to fetch approvers from R/3 comparing item cost centre in detail.

Regards,

Sateesh