error message

I get this error from now and then, it works fine 99 times of 100 and is wery irritating

Warning: main(http://www.xxx.se/extern.php?action=new&show=5&fid=3): failed to open stream: HTTP request failed! in /customers/xxx.se/xxx.se/httpd.www/index.php on line 90

Warning: main(): Failed opening 'http://www.xxx.se/extern.php?action=new&show=5&fid=3' for inclusion (include_path='.:/usr/lib/php') in /customers/xxx.se/xxx.se/httpd.www/index.php on line 90

Im using extern.hp with TGO´s extension this one
http://punbb.org/forums/viewtopic.php?id=7552

And also Codexp´s latest posts on index mod:
http://punbb.org/forums/viewtopic.php?id=10942

The errors are when my headlines tryes to load and puts out a error of abowe

I dunno if i have extremely many queries and my db gets overloaded, but something is it. Later when i refreshes the page it works fine