Forum vb4 upgrade hangs on step 11 of vb4alpha1 upgrade script
 

Before anyone flames me, we had a test enviornment, made an exact copy of the site, successfully upgraded to vb4 and it worked just fine. We developed the skin, plugins ...everything.
Now we're ready to upgrade the actual site to vb4.
I uploaded all the files, ran the install script and it keeps hanging on step 11 of the first update script (upgrade_400a1.php?step=11)

The page keeps either timing out or gives me a mysql error (which is below). (Note: in my previous update it actually went past this page and worked just fine!
What can I do? How can I skip this step or work around it?

Here's the error:

• Creating index threadid_visible_dateline on post
• Creating index ipaddress on post
• Creating index dateline on post

Database error in vBulletin 3.8.4:

Invalid SQL:
ALTER TABLE post ADD INDEX dateline (dateline);

MySQL Error : Duplicate key name 'dateline'
Error Number : -1
Request Date : Thursday, December 31st 2009 @ 07:38:52 AM
Error Date : Thursday, December 31st 2009 @ 07:42:40 AM