Заменить строки
<cfset postBody = postBody & "client_id=" & UrlEncodedFormat(this.clientid) & "&">
<cfset postBody = postBody & "client_secret=" & UrlEncodedFormat(this.clientsecret) & "&">
<cfset postBody = postBody & "redirect_uri=" & UrlEncodedFormat(this.callback) & "&">
с
<cfset postBody = postBody & "client_id=" & UrlEncodedFormat(application.clientid) & "&">
<cfset postBody = postBody & "client_secret=" & UrlEncodedFormat(application.clientsecret) & "&">
<cfset postBody = postBody & "redirect_uri=" & UrlEncodedFormat(application.callback) & "&">