SMPP default charset ?

[BeCauet]

Hello,

If I send via PHP UTF-8 script:

/cgi-bin/sendsms?text=hello&charset=UTF-8&coding=0

By default, in what "charset" Kannel send the SMS in a SMPP connection?

WINDOWS-1252 ?
UTF-8 ?
GSM 03.38 ?
ISO-8859-1 ?


Please help...
Thank you.