FileUpload control not working in firefox

hi,
Iam using a FileUpload  server control in my website..
  Iam retrieving the path of the File using  "FileUpload1.postedFile.FileName"
In Internet Explorer I get the real path of the File..    "Eg:D:..\test.txt"

But In Frefox Iam not getting the Full path of the file .just the File name  "Eg: test.txt" 
Plz give  me a solution For this..
 
 
Thanking In advance..
 
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