Jasmin not sending mulitpart sms

[israjet]

When trying to send a message longer than 160 characters (GSM7 encoding) through either the REST or the HTTP APIs, the recipient only gets the first 153 characters, regardless of the configuration being:

# How many message parts you can get for a long message, default is 5 so you
# can't exceed 800 characters (160x5) when sending a long latin message.
long_content_max_parts = 5

# Splitting long content can be made through SAR options or UDH
# Possible values are: sar and udh
long_content_split = sar

(extract from my /etc/jasmin/jasmin.cfg file)

REST API payload:

{
    "from": "{{from_param}}",
    "to": "{{to_param}}",
    "content": "Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium quis, sem. Nulla consequat massa quis enim. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. In enim justo, rhoncus ut, imperdiet a, venenatis vitae, justo. Nullam dictum felis eu pede mollis pretium. Integer tincidunt. Cras dapibus. Vivamus elementum semper nisi. Aenean vulputate eleifend tellus. Aenean leo ligula, porttitor eu,"
}