No-one has extra info on the partyline, I never give users extra info...everyone get's the welcome msg and for everyone it is the line as posted above here. And it's not a script, as they already got the line when the bot run for the first time.
Well, for the last 4 years, I have looked deep into eggdrop, both to see what is going on, what can be imroved, and to try and locate anoying bugs.
In this time, I am yet to find anything like this, bundles either inside the core, it's modules, or any of the included scripts.
Can I ask where you obtained the copy of eggdrop from?
Are you sure you can rule out the script you have installed?
Have you tripple checked?
Quad checked?
There is no doubt in my mind, that it is either a script you currenly run, or one you have had running between first startup, and now, but has not been cleared from memory properly.
Try issueing a ".restart". This will clear anything that was in memory. If it re-occurs, then it is a script that hasn't been unloaded.