append UDH with message _payload value

[Shayan shah]

Hi,

I am configuring kannel for a an operator over SMPP. The operator wants to send 
the multi-part message as binary in message_payload TLV. I have successfully 
configured this, but they also need the UDH to be appended to the beginning of 
the content of message_payload, like 
'0500030103014f6b207175697420706c6179696e2077697468207468652073636973736f727320616e6420736874
 with 'udh in bold'. I have done lot of search on web but didn't found any 
solution. Any suggestions how to achieve it?

thanks