Fieldvalues filter with comparison operators

We would like to get contacts filtered on a custom field id 7 that has values between 10 and 90. We tried several options in API v3 like this:

https://myname.api-us1.com/api/3/fieldValues?filters[fieldid]=7&filters[val][gte]=10&filters[val][lte]=90&include=owner

But not working yet. Anybody ideas?