Sorry chaps... I misthought. Further up the script I use some of my own modules, and in one of those modules I have a

print header;
[download]

for debugging purposes... which was overriding my nice application/pdf header further down, hence the garbage. So, for the record, my snippet above DOES do what it says on the can... if you have the right can opener. Thank you for listening.

§ George Sherston