accessing prepared data after the validation

[eluser]EugeneS[/eluser]
as was said in this topic
http://ellislab.com/forums/viewthread/158619/

it is supposed to have inside $this->input->post('field_name')

already prepared data after validation, but its not so, at least when i'm using trim rule, after the successful validation i still see not trimmed data (with the white spaces in the beginning and in the end of the string)