[squid-users] squid not parsing URLs

[Rolf]

hello
I have a new install of squid and I have done very little customisation 
of the config (just things like the  cache directory, cache_peer and 
acls). Most of those settings were copied from an old (2.5) squid 
install that worked perfectly.

I am having troubles with this box with lots of different sorts of urls
but the most common type is where a url contains a question mark prior
to some further part of the url
What happens is that squid comes back and says 'connection refused'
quoting the url only up to the question mark.
An example. If I go to this site  http://www.osnews.com it loads fine,
then I click on this link
/http://www.osnews.com/comment.php?news_id=3D8343
squid returns:
While trying to retrieve the URL: http://www.osnews.com/comment.php?
The following error was encountered:
         Connection Failed
  The system returned:
     (111) Connection refused
  The remote host or network may be down. Please try the request again.
In access.log it shows
TCP_MISS/503 1504 GET http://www.osnews.com/comment.php? - NONE/- 
text/html

If I sniff the conversation the relevant http packet begins with "503 
service unavailable"

I can't work out why this is so and what if any config in particular I 
need to have.
 Any help gratefully appreciated.

Using squid 2.5stable6 on debian.
Thanks
rolf.