JavaScript Error when Creating New Context

Steps to replicate the problem:
1) Click the 'New' link to create a new context via Agile tab > Planning Board
2) Enter the context name and set the ranking field as 'Ascending'
3) Click 'Save and Apply'
4) There is nothing happens after clicking the button.
5) The javascript error window pop-up.

Additional information:-

• The JavaScript popup error is only present in Internet 6.
• In IE8, there is no popup, only a yellow javascript warning in the bottom left corner of the browser. The content of this error is in the attachment NewContentError.txt.
• In Chrome, no error, no popup, just nothing happens when saving.