I just installed ubercart 2.
I have a custom CCK content type with CCK fields like price, art. number etc.
These fields are synchronized correctly between translations:
for ex. if I change the price in one language, the other languages are updated correctly.
I added my cck content type to ubercart by creating a class. The new fields like SKU and sell price are not updated correctly between translations.
The default uc_product content type has the same problem.
After I created an English product node I selected translate. The fields SKU and sell price are set to default, empty and 0.00. Normally, the field values of the source node should be displayed.
So my D6 installation works properly regarding i18_sync en CCK, but Ubercart does not.