jQuery UI 1.9m6 Submenue does not rendet correctly (overlay = false ?)

Good evening,

I have a problem related to the latest Milestone release of jQuery 1.9.

If I click on a jQuery button, I get a submenue behind other Elements on the webpage.

To understand my concern better, I have added a picture to my topic:

http://forum.jquery.com/viewImage.do?fileId=14737000002774349&forumGroupId=14737000000003003

How can I fix this behaviour ?

I just want to see the full menue "overlayed" (above) all other elements.

I have created a demo application:

http://www.file-upload.net/download-3797550/PHPDE.zip.html

Tested on Debian & Google Chrome 13.

Thanks in advance for your spended time !