Can you try to send with DataCoding
ALT.SMS.DataCodings.Latin1 or
ALT.SMS.DataCodings.UCS2 ?
Realy SMPP client never use GSM coding. Conversion to GSM is performed only on SMSC side.
Depending on the chosen ESME data coding the short message text data is send from the SMSC to the mobile in one of the following ways:
• Transparently
• Mapped to the default GSM alphabet
When text is send from ESME to SMSC in USC2 coding the data will be transparently send to the mobile.
When the text is coded for example in LATIN-1 or the SMSC Default Alphabet, usually a mapping will be performed by the SMSC to the GSM Default Alphabet before sending the text to the mobile. As the GSM Default Alphabet is 7-bit coded and uses other codes for some characters and in some cases does not even provide a certain character, this implies that during the mapping process not every character can be mapped one-to-one.