I am trying to get my CGI scripts running on my web host (which runs on FreeBSD). To debug why I keep getting the dreaded "premature end of script headers" error, their support recommended that I redirect all my output to stderr, rather than `print`ing it. Looking up how to do this, I came across a very old [RAMBO ticket](http://www.rebol.net/cgi-bin/rambo.r?id=4032) about it, but it looks like it was never implemented. 

Per some of the answers to [this question](https://stackoverflow.com/q/2990414/2486583), it seems like I should be able to do a `call {echo Hello, world >&2}` to achieve this, but it doesn't work.

How can I write to stderr in REBOL2?