In order to display online/offline status next to usernames, change the code below in chat.php:
<a href="#talk" contact="<?php print $contact->ID; ?>" title="<?php ( $contact->chat_last_activity > ( time() - ( 2 * $contact_timeout ) ) ) ? printf( __( 'talk with %s', 'chat' ), $contact->display_name ) : printf( __( 'send offline message to %s', 'chat' ), $contact->display_name ); ?>" class="talk"</a>
to:
<a href="#talk" contact="<?php print $contact->ID; ?>" title="<?php ( $contact->chat_last_activity > ( time() - ( 2 * $contact_timeout ) ) ) ? printf( __( 'talk with %s', 'chat' ), $contact->display_name ) : printf( __( 'send offline message to %s', 'chat' ), $contact->display_name ); ?>" class="talk <?php print ( $contact->chat_last_activity > ( time() - ( 2 * $contact_timeout ) ) ) ? 'online' : 'offline'; ?> <?php if( $odd != $odd ) print 'odd'; ?>"><?php print $contact->display_name; ?></a> <span class="status">(<?php print ( $contact->chat_last_activity > ( time() - ( 2 * $contact_timeout ) ) ) ? 'online' : 'offline'; ?><?php if( $odd != $odd ) print 'odd'; ?>)</span>
Also, add the styles below to chat.css:
#chat-contacts a.online:link {
color:#ff0000;
}
#chat-contacts a.online:hover {
color:#ff0000;
}
#chat-contacts a.online:visited {
color:#ff0000;
}
#chat-contacts a.offline:link {
color:#aaaaaa;
}
#chat-contacts a.offline:hover {
color:#aaaaaa;
}
#chat-contacts a.offline:visited {
color:#aaaaaa;
}
.status {
font-style: italic;
color:#666666;
}