ecommerce oacs-5-1 branch has many additions that have not yet been added to oacs-5-2 branch.
To update the oacs-5-2 branch of ecommerce, I suggest this approach:
Determine the differences between the oacs-5-1 branch bewteen 2005 Feb 24 and now, then manually apply the changes to the oacs-5-2 branch.
I back ported most of the changes in the oacs-5-2 branch to oacs-5-1, but did not forward port any changes, because there were massive changes going into dotlrn-ecommerce, and I did not want to mess up any ongoing development that depended on ecommerce.
Hope this helps,
Torben