IE: Document picker - Option 'open in new window' don't trigger the OK button

STEPS:
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• as author link the word 'body' from myarticle1 to myarticle2
• save, done
• click the 'internal link' button again
• check the option 'Open in new window'
  EXP: on Firefox, the OK button becomes available
  ACT: not on Internet Explorer v7 or v8

Note: the same applies when unchecking the option.