Some MaterialData constructors are deprecated?

In the 1.6.4 recommended builds for craftbukkit, they have deprecated the constructors for creating MaterialDatas with bytes casted to data values. This has in turn affected the .addIngredient() method that uses Materials and bytes casted to data values. I'd like to know why they've done this, and what I can do to work around it when using the .addIngredient() methods.