Plugin breaks get_post_meta function for product variations

Hi there,
I’ve found that the WCML_Attributes::filter_product_variation_post_meta_attribute_values_in_current_language function breaks the get_post_meta function for product variations. This function is a filter callback for the get_post_metadata filter that translates variation attributes.
The problem is that it returns a value from the cache for all metakeys, regardless of whether the metakey is an attribute.

This is how you can reproduce the problem:

$metadata = get_post_meta( $variation_id ); //This call to the filter function stores the meta in the cache.
update_post_meta( $variation_id, '_dummy_value', 'val'); // Add a meta for the product variation.
$metadata = get_post_meta( $variation_id ); //This should returns all meta data that should include  _dummy_value, but it does not contain it because the WCML_Attributes filter returns a value store in the object cache.

A workaround is to clear the cache in the update_post_meta action.

Could you fix this bug? Thank you.