Purchase contract history at item level.

Hi Experts,

Has anyone come across any function module to get the Purchase contract item level history ??? i.e. Item level history containing bid invitation no, shopping cart no.

Also, my observation is that in SRM screen PO line item contains line item level history of documents & Purchase contract has only header level history which is present in "Document History". Any idea why is it so ???

Would appreciate +reward points if anyone could answer my queries.

Thanks in advance,

Rajeshree