Make in_array like query with MongoDB in PHP - codeigniter

Question

I am building a web app and in this app (Codeigniter and MongoDB) I let people search files by tags. For example if they enter the tags house and cat they get all files matching them. The tags are collected in an array ($tags).
This is how I do the find query:
select ($select) -> where_in_all ('tags', $tags) -> get ('uploaded_files');
The above query works fine but I really need to let the users search by partial tags. Like "hou" instead of "house". I know how to make a like query but only for one tag at a time. How can I make the in_array search work?
I am using the excellent MongoDB wrapper by vesparny. This is the code in that wrapper for a normal in_array search:
public function where_in_all($field = "", $in = array()){
$this->_where_init($field);
$this->wheres[$field]['$all'] = $in;
return ($this);
}
This is my attempt at modifying it which does not work:
public function where_in_all_like($field = "", $in = array()){
$this->_where_init($field);
$this->wheres[$field]['$all'] = new MongoRegex('/'.$in.'/i');
return ($this);
}
What am I doing wrong?
The wrapper can be found here:
https://github.com/vesparny/cimongo-codeigniter-mongodb-library
Thankful for all help!
Update
This seems to work BUT only on my local server... Not on the production server.
public function where_in_all_like($field = "", $in = array()){
$newarray = array ();
foreach ($in as $value) {
array_push ($newarray, new MongoRegex('/'.$value.'/i'));
}
$this->_where_init($field);
$this->wheres[$field]['$all'] = $newarray;
return ($this);
}
Update 2
I updated MongoDB on my server to 2.0.4 and it works fine now.