i get an error message with theme: Fatal error: Cannot redeclare phptemplate_username()

I get this err. message once i enable my theme: Fatal error: Cannot redeclare phptemplate_username() (previously declared in /home/inst/public_html/user/sites/all/modules/realname/realname_theme.inc:20) in /home/inst/public_html/user/sites/all/themes/clearblue/template.php on line 44

i suppose its messing with this code in the theme:

/*****************************************************************************
Override theme_username() function to remove "(not verified)" from comments.
*****************************************************************************/
function phptemplate_username($object) {
if ($object->uid && $object->name) {
if (drupal_strlen($object->name) > 20) {
$name = drupal_substr($object->name, 0, 15) .'...';
}
else {
$name = $object->name;
}

if (user_access('access user profiles')) {
$output = l($name, 'user/'. $object->uid, array('attributes' => array('title' => t('View user profile.'))));
}
else {
$output = check_plain($name);

Any idea on how to remove this, am also looking at the previous versions of realname as comented on other some what similar issues.
Thanks in advance