Regression: Unable to save a document in IE8

When using IE8 it is not possible to Save or Save and Close a doucment in the CMS.

Steps to reproduce (in gogreen)
1. login and go to documents
2. add a new document
3. enter a title
3. click Save
Expected: The document is saved.
Actual: The document is not saved and it is no longer possible to navigate to another document.

A similar problem occurs when saving the document while leaving the (mandatory) title empty.

In the javascript console the following error is logged:
jquery-1.11.0-min line 3 character 11407
Member not found
The contents at that position in the javascript is:
this.isDefaultPrevented

Found as part of "Basic editing document" of Testplan 7.9 - FCS