[eluser]dmorin[/eluser]
If you define a field to be validated using the form validation library and it isn't included in the $_POST array, the form validation library will still validate it including running any callback functions, but will not add the processed value back into the $_POST array at the completion of the validation.
Further, since the set_value() function DOES correctly output the field (though form encoded?), it seems as though the validation library is acknowledging that it's valid, which seems to indicate that it be available through the accepted way to retrieving the validated information
