Mapping custom fields to multiple target fields

As a work around to the inability to print the description field in reports, we have created a custom field to hold a short description of the task. This field can then be included in reports along with the task title.
We populate the custom short description field from a Request Form which creates a new task in designated folder. It would be great to be able to populate both the custom field and the Description field of the new task from one 'question' on the report form.