OP_SpecialMessage
 

I was poking around with this tonight (Underfoot client) and think I have figured out a few things.

The header has 3 bytes

byte 1: controls the format (arrangement) of the message
byte 2: controls whether the message is logged to the journal
byte 3: controls the language

Examples use "Fred" as the npcname, and "message" as the passed message

Example of byte 1:
0 message
1: Fred says message
2: Fred shouts message
3 message
4 Fred message
5 Fred tells the group message

Examples of byte 2:
0: not logged
1: logged
2: logged
3+ not logged

Byte 3 is the normal language numbers (ie 3 is Elvish)

Messages are garbled based on language skill.

What I was really hoping to find was a way to log something without saying it out loud. Looks like no dice.

Saylinks are logged as a long string of chars (log does not format links)
So there does not appear to be a way to log text using saylinks and have the logged version cleaned up.

If I could have logged without speaking, then I could send the message twice. Once to display with the link, and once to log with the cleaned up text. Alas, no.