modiffy simple php script

[login to view URL] this is my script so it post same text to 2 different xml you can see demo here [login to view URL] (go to [login to view URL]) SO what you need to do: example when i add new post it add at top of xml can you make a way i can chose example to add in any part of xml example after a or after b or .... ... I WILL CHOSE LOWEST BID _______________ <rss xmlns:xs="[login to view URL]" version="2.0"> <channel> <item> <title>a1</title> <enclosure url="a2" type="image/jpeg"/> <description>a3</description> <link>a4</link> </item> <item> <title>b1</title> <enclosure url="b2" type="image/jpeg"/> <description>b3</description> <link>b4</link> </item> </channel> </rss> __________________________ <channels> <channel> <title>a1</title> <img>a2</img> <info>a3</info> <url>a4</url> </channel> <channel> <title>b1</title> <img>b2</img> <info>b3</info> <url>b4</url> </channel> <channel> ________________________________