The ezdate fieldtype does not save the value. The current date is always saved instead of 

Steps to reproduce

Go to Product catalog > Product Types and Create a new product Type.

Add a DATE fieldtype in its fiels definition and save

Create a new product form the product Type jou have juste created, set the date attribute to whatever date except current date and save

Check in the product details tab that the date you have set has well been saved

Then edit the product, you will notice that the date has been replaced by current date (today)

Expectation:

The date field should keep the registered date