Currently, when I want to send a message through the tsf_send_message stored procedure with a parameter that contains non-latin characters, such as Cyrillic and Thai, these characters are all converted to question marks.
i.e. <TEXT>"ภาษาไทย Phasa thai"</TEXT> becomes <TEXT>"??????? Phasa thai"</TEXT>.
However, as was noted in the answer to the related question, by changing the datatype of the tsf_send_message function from varchar to nvarchar, the use of non-latin characters in parameters will become possible.