XML : can XJC ant task using MOXy JAXB Implementation

I wondering is there is a possibility of using xjc ant task with Eclipselink MOXy as jaxb implementation.

I ran into an issue where XJC generate source code with out required=false for nillable attribute. MOXy expects required=false for Nullable fields.

My Code generation is using XJC task from RI , If I change this to use eclipselink\bin\jaxb-compiler.cmd it solves the problem but requires a lot of changes.