Would like to have certain feilds prepopulated on subtasks from the parent issue

It would be really nice if you could set up fields on a sub-task to autopopulate when you create the subtask from the parent issue. For instance, I have a user story issue type. When we create the subtasks required to do the work in an interation, I have manually select the fix version for every subtask of teh parent story. It would be really nice if by default it set the fix version to the fixversion from the parent issue (the user story). The user could then change it if needed but it would be great to have that pre-filled by default.