rss + .php extension

I was trying out Carp and couldnt understand why it didnt work with any feeds that have .php extensions. Extensions like .xml, .aspx and .rdf all seem to work fine.

 

Were you feeding it as XML or RSS (either through Apache, or using the header function in PHP)?

 

i am using it in my php pages, for example, this works.
CarpCacheShow('http://newsrss.bbc.co.uk/rss/sportonline_uk_edition/football/rss.xml');
but feeds that end in .php doesnt work in this format.