VERIFIED SOLUTION i

In Portrait Dialogue, SMS messages with accented characters can only be sent with up to 70 characters. It is not possible to use an encoding set to take advantage of 160 characters limit per message.

Issue

SMS messages with special accented characters can only be sent with up to 70 characters. It is not possible to use standard encoding set to take advantage of 160 characters limit per message.

For example - Spanish text message:
User-added image

Message received on the phone:
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Messages in languages like Spanish, Russian, French have to be send in Unicode even though these special characters are supported in the extended ANSI character sets Windows-1252.
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Attempts to replace missing language characters in GSM 7-bit alphabet such as
:
¿ = %60
ñ %7d
will fail because not all characters are available (for example: á).
 

Cause

This is dependent on what is supported by the SMS service provider in the specific installation.
There is no common protocol for sending SMS from an application like Portrait Dialogue and all installations have different SMS output channel plugins which are created by Professional Services during installation and/or configuration and use different third-party SMS service providers.
The individual SMS service provider
decides what character sets are supported and the maximum length of the messages.

Resolution

UPDATED: April 6, 2017
This matter should be individually discussed with the SMS service provider.