You have a syntax error in your script.

It says:
if (!isset($usuario) OR $usuario != $login (...)
                                 ^^
It should say:
if (!isset($usuario) OR $usuario !== $login (...)
                                 ^^^

Not enough information was provided for us to be able
to handle this bug. Please re-read the instructions at
http://bugs.php.net/how-to-report.php

If you can provide more information, feel free to add it
to this bug and change the status back to "Open".

Thank you for your interest in PHP.


..and doesn't really look like any bug, just misunderstanding  about how things work..

Hello.

   The same problem happened in php 4.3.1. Anyway, let me explain you
better why I think it may be a bug.
   First, why should it be '!==' instead of '!='?! I'm not comparing
types, only the value!
   I have this 'if' that should be "false" (i tested the values) and
always returns "true"
   To check if it was a sintax error (before my 1st post), i tryed
this:
<?
$x = 0;

if (!isset($usuario))
     $x = 1;
if ($usuario != $login)
     $x = 1;
if ($usuario == 'logoff')
     $x = 1;
if ($user_senha != $senha)
     $x = 1;
if ($user_senha == 'null')
     $x = 1;

echo $x;
?>

At this point I've got what I expected.
My next step was to remove the "echo $x" and put $x into an if.

<?
if ($x) {
     echo "It's true! \$x == $x";
}
?>

And guest what?! The value of $x become 1!!!!
So I changed the if to:
if ($x == 1)
And $x became 1 again.
So, I tried:
if ($x == 0)
And $x became 0!!!

As you can see, I used "==", not "="! And, again, I don't whant to check
the types!

I've put back the "echo $x" before "if ($x)", and now it worked fine! No
errors at all!

I tried to use some else case, and wrote it:

<?
if ($x) {
     echo "It's true! \$x value is $x";
}
else {
     echo "It's false! \$x is $x!";
}
?>

Now, gess what was the output?!
"It's false! $x is 0!";

Can you belive it?! Maybe it's a hardware failure or something, but it
just happened in this unique file!
index.php
And also, it uses session.
I didn't wrote the entire code and it was working in a win98 machine.
I've put it in a server with php 4.2.3 and worked.
I haven't tested it in my machine with this version of PHP.

I gess it's all now.
Sorry about my 1st post.
Sorry cause I posted 2 times this one.

best wishes.

Sorry, but your problem does not imply a bug in PHP itself.  For a
list of more appropriate places to ask for help using PHP, please
visit http://www.php.net/support.php as this bug system is not the
appropriate forum for asking support questions. 

Thank you for your interest in PHP.

.

I fixed the erros with session - my buddy mad a lot of mistakes - and It started working.
The problem isn't with the 'if' and 'else' case, but with error handling in session.

well, anyway, tx about your patience.

OgRo