[TYPO3] TYPO3 4.1.1 Cannot delete pages

[dieter orens]

When trying to delete pages in the page-tree, something strange happens.

The main frame get re-initialized and I get a javascript error:

uncaught exception: no permission to read the window.nav_frame property.

It is a fresh installation and I had no problem like this with Typo3 4.0.4.

It happens in IE as well as in Firefox.

Anybody a clue?