Where/what is $errormessage ?

[tm21]

I want to edit my redirect page to change the standard phrase after you make a post to something different. I see the phrase name for this is $vbphrase[postthanks]. Since I have seen it recommended you create a custom phrase rather than edit an existing one, I was going to do that. When I look at the STANDARD_REDIRECT template all I see is the code $errormessage where I would expect the postthanks bit. The page renders the postthanks phrase, so I suspect $errormessage must contain the proper postthanks code within it. However, I have found no such thing as what $errormessage is anywhere within the vb software. Is this a phrase, a template, or something else?

I figured I would replace the postthanks with my custom phrase in the template, but I can’t do that if I don’t know where it is. I would replace the $errormessage part, but I don’t know what functionality I may screw up since I can’t see what $errormessage actually is.