There is indeed a limit for the auto-response. Though the limit should be high enough for basic use.
If you want an "unlimited" amount of sentences to reply with, then you need to create a script.
There might already be scripts out there which does exactly that though; providing a more elaborate auto-response system. Search the
scripting database for it, or search the
scripting subforum.
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In fact, you could also combine the build-in auto-responder with a script since the build-in auto-responder can also respond with a command. And you can use the /script command to call a function from a script.
Putting those two together, you could create a rather small script which does nothing more than providing you a random sentence (out of thousands) just by calling its function with the /script command.
Example:
JScript code:
function RandomAwayMessage() {
var Quotes = [
"Sorry, I'm away.",
"I'm sooo away",
"I'm not here",
"Gone..."
];
return Quotes[Math.floor(Quotes.length*Math.random())];
}
And in the preferences of the auto-responder of Messenger Plus! you type as sentence:
/script RandomAwayMessage
Note that in this small script example the sentences are choosen randomly, thus not in sequence like with the basic auto-responder. Of course, with a more elaborate script, you can program the behaviour in any way you want.
/ 
