How to decode SMPP message body as GSMSIM?

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Hi guys, Here is the case, we have capture with SMPP protocol but the SMS body is shown as raw bytes and there is no way to decode it as GSMSIM. I also tried to enable GSMTAP but it's bound strictly to UDP. So, there is no option to decode SMS body as GSMSIM. Could you add GSMSIM to the Data coders as it's only data by nature and allow GSMTAP on TCP as well?