[Mediawiki-l] Missing session_start in SpecialUpload?

[Stephen Warren]

I recently installed mediawiki 1.5.6 on apache 2.0.53 and php 4.3.11 on 
Fedora Core 3.

I've been having issues with the Special:Upload page, when attempting to 
upload a new version of a file that already exists. It seems that some 
data is passed from the file upload the first time it's hit (which saves 
the upload to a temp file) to the confirmation page via the $_SESSION 
variable.

However, $_SESSION isn't getting set on the confirmation page (or 
rather, the page that's invoked when I click the "save anyway" button on 
the "do you really want to save over the existing file" page)

It seems that there's a missing call to session_start...

If I edit includes/SpecialUpload.php, class UploadForm, function 
UploadForm (constructor) and add "session_start();" prior to first 
referencing $_SESSION, then everything works just fine.

Is this really a bug, or do I have something horribly screwed in my 
configuration? Looking back at the CVS history, the usage of $_SESSION, 
especially isset( $_SESSION['wsUploadData'][$this->mSessionKey] ) dates 
back about 14 months, which seems a long time for this to have gone 
unnoticed?

Any pointers appreciated. Thanks.