[NTG-context] Defining a function

I defined a command as descriped in http://wiki.contextgarden.net/Processing_Lists. (\def\IHaveTo#1#2{I have to #1 on #2.\par}) If I define it in the tex-file that is processed it works. But when I put the definition in the template file that is used, it does not work. What do I need to do to define a command in a template file? -- Cecil Westerhof