File upload does not work in Safari 5.0

Cannot upload content using Alfresco 3.3 Web Client with Safari 5.0 on Mac
Problem Description:

1. Start Safari
2. Open the Alfresco 3.3 Web Client
3. Log in as admin
4. Create a space
5. Click Add Content
6. Click Browse and select any file
7. Click Open from the file selection dialog
8. The next screen shows Upload Content and a couple of headings but does not show the expected dialog allowing the user to enter General and Other properties. The Ok button is grayed out. (see attached screenshot).

P.S. This works with Safari 4.0, but does not work with Safari 5.0.