Insert Term Question

Hello!

I am trying to import a CSV File into custom content types in WordPress 3. It works fine, only I am trying to create new terms in my custom taxonomy for the values in one of the CSV Columns.

It seems that I cannot insert new terms using wp_insert_term from anywhere except within the init() stage of WP.

When I use the following function, it will not add:
/** Upload **/
$uploaded= @$_POST[‘hidden_uploaded’];
$content_type= @$_POST[‘content_type’];
$csv_file= @$_FILES[‘file_csv’][‘tmp_name’];

if(isset($uploaded)){
$result = price_read_csv($csv_file, $content_type);
$category_id= wp_insert_term(‘Containers’, ‘price_products_category’);
echo $result;
}

This is in the main plugin file, so basically if the $uploaded variable is set (after the user submits the upload form) it runs the csv function and tries to add a hard coded category… However this will not work, do new terms have to be added at a particular stage or can they can be added when needed?

Thanks much!!