problem with newly added custom field!!

i have installed opencart and i was trying to add a custom field in usr registration page,,but its showing error after regi,,any idea how to solve it?

Notice: Undefined index: address in /home/rapid/public_html/demo/catalog/controller/account/register.php on line 281
Fatal error: Unsupported operand types in /home/rapid/public_html/demo/catalog/controller/account/register.php on line 281


thanks

Find
$data['register_custom_field'] = $this->request->post['custom_field']['account'] + $this->request->post['custom_field']['address'];

Replace
if(isset($this->request->post['custom_field']['address'])){
$data['register_custom_field'] = $this->request->post['custom_field']['account'] + $this->request->post['custom_field']['address'];
} else {
$data['register_custom_field'] = $this->request->post['custom_field']['account'];
}

thanks,,,problem solved,,also there are some bug in custom field uploader php file,,,i hope we will not get those bugs in next update ..