Multiple headers not being added

I am using a script that adds multiple headers but only the last one is added. I tried moving headers around and changing format (space rather than tab for example) but the behavior is consistent: only the last addHeader is added. Is this an issue with H2?

To make sure it was not a script error, I used the example on the thread

The result is that only the last addHeader is added (and the UA is not changed)

Is there something wrong with my script?

setHeader UA-CPU: none-ya
addHeader xPat: My-Header
addHeader Pragma: akamai-x-cache-on