Please do not submit the same bug more than once. An existing
bug report already describes this very problem. Even if you feel
that your issue is somewhat different, the resolution is likely
to be the same. 

Thank you for your interest in PHP.

Search before submitting a bug, we will also NOT change this until there is a browser that borks on this. Also, you can change this in php.ini if you really want to do this.

> Please do not submit the same bug more than once. 
> An existing bug report already describes this very 
> problem. 
 
Please, could you post the number? I searched for 
"arg_separator" ... do you mean #27965? - sorry, I thought 
that it is marked as bogus because it is a duplicate of 
#15504, so I did not read that thoroughly. My fault. 
 
> we will also NOT change this until there is a browser 
> that borks on this. 
 
I am sorry, I (and m-w.com) do not know the word "bork" - 
is that typo? 
 
And what is more important, some broken (?) browser or html 
standard, parsers and good browsers? 
 
> Also, you can change this in php.ini if you really want 
> to do this. 
 
Yes. And I can fork the php codebase and make a version 
which behaves correctly - my report was about changing the 
default and not about what can I do with my php.ini 
... I do not see any reason for making the wrong behaviour 
default. 
In addition, as mentioned in #27965, not everyone has the 
possibility to change the defaults, and many webmasters 
leave the default settings untouched because they believe 
that these are optimal or simply because they do not 
understand that. :-(

You can use ini_set() too for this, if you use it before using session_start(). We are not going to change the default.

I understand that you won't change the default setting of arg_separator. What surprises me is that one of the finest open source applications is shipped with a default that breaks the W3C standard. People are complaining at Microsoft for breaking standards. Wouldn?t the right decision be to show MS that we can do better? Why not ship a product that does adhere to the specification?

I know that you can change arg_separator in the php.ini, but most sites just run the vanilla php.ini. Wouldn?t it be great if we could help them produce standards compliant sites? The use of ini_set forces people to fix something that shouldn?t be broken in the first place and it doesn't work for code that uses ini_get to get the separator (like Pear Net_URL).