REST controller wrong output

[eluser]oskar_ha[/eluser]
Hi all.
I use REST server for GET request. When I try to output some strings value, I get wrong output.

Code:

$this->response(array('id'=>'012e0098'), 200);

output:

Code:

{"id":1.2e+99}

How to get correct ouput string?

Code:

{"id":"012e0098"}