How to send php headers?

[fripsy]

Hi All,

Some pages from my site need to be displayed on another site in an i-frame. As this is blocked by the "X-Frame-Options:SAMEORIGIN" header, I need to change that header on only those pages.

I know how to send php headers, I just don't have a clue as to where I should insert that header.

Thanks.

PS. I tried inserting at the beginning of the template, but there seems a lot of stuff going on before the template is called...