I have done some testing with another thread where a problem like this was occurring. It seems that the force decimals setting was not set properly in the cart object. If you can please post back with a copy of your cart page from inside of the WA_eCart folder. The file will be named after your cart with an _PHP.php at the end. You can add this to a zip archive and attach it to your response. I will need to examine this file and do some testing on it. Please also post back with the version of DW you are working with and the OS so I can ensure that I'm replicating your environment.