CCM Catalog Upload changing case of Supplier part Number

We are using Contract Management in conjunction with Catalogues. When we load the data into the contract the supplier part number is coming through correctly eg i99942 but when loading into the catalogue the same item becomes I99942 although the same data source is being used. When you then try to shop for the product it is not able to find it in the contract.

What do I need to do to resolve this issue?

Nick J