diff --git a/mozilla/widget/public/nsIFilePicker.idl b/mozilla/widget/public/nsIFilePicker.idl
index d5690b890a6..812826bd2d7 100644
--- a/mozilla/widget/public/nsIFilePicker.idl
+++ b/mozilla/widget/public/nsIFilePicker.idl
@@ -76,6 +76,13 @@ interface nsIFilePicker : nsISupports
   /* what is this? */
   attribute wstring defaultString;
 
+ /**
+  * The filter which is currently selected in the File Picker dialog
+  *
+  * @return Returns the index (0 based) of the selected filter in the filter list. 
+  */
+  attribute long filterIndex;
+
  /**
   * Set the directory that the file open/save dialog initially displays
   *
diff --git a/mozilla/widget/src/windows/nsFilePicker.cpp b/mozilla/widget/src/windows/nsFilePicker.cpp
index 28e09520148..63543b9f611 100644
--- a/mozilla/widget/src/windows/nsFilePicker.cpp
+++ b/mozilla/widget/src/windows/nsFilePicker.cpp
@@ -308,6 +308,25 @@ NS_IMETHODIMP nsFilePicker::GetDefaultString(PRUnichar **aString)
   return NS_ERROR_FAILURE;
 }
 
+//-------------------------------------------------------------------------
+//
+// Set the filter index
+//
+//-------------------------------------------------------------------------
+NS_IMETHODIMP nsFilePicker::GetFilterIndex(PRInt32 *aFilterIndex)
+{
+  // Windows' filter index is 1-based, we use a 0-based system.
+  *aFilterIndex = mSelectedType - 1;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsFilePicker::SetFilterIndex(PRInt32 aFilterIndex)
+{
+  // Windows' filter index is 1-based, we use a 0-based system.
+  mSelectedType = aFilterIndex + 1;
+  return NS_OK;
+}
+
 //-------------------------------------------------------------------------
 //
 // Set the display directory
diff --git a/mozilla/widget/src/windows/nsFilePicker.h b/mozilla/widget/src/windows/nsFilePicker.h
index 7dc17efa900..275118133e7 100644
--- a/mozilla/widget/src/windows/nsFilePicker.h
+++ b/mozilla/widget/src/windows/nsFilePicker.h
@@ -51,6 +51,8 @@ public:
   NS_IMETHOD SetDefaultString(const PRUnichar * aDefaultString);
   NS_IMETHOD GetDisplayDirectory(nsILocalFile * *aDisplayDirectory);
   NS_IMETHOD SetDisplayDirectory(nsILocalFile * aDisplayDirectory);
+  NS_IMETHOD GetFilterIndex(PRInt32 *aFilterIndex);
+  NS_IMETHOD SetFilterIndex(PRInt32 aFilterIndex);
   NS_IMETHOD GetFile(nsILocalFile * *aFile);
   NS_IMETHOD GetFileURL(nsIFileURL * *aFileURL);
   NS_IMETHOD Show(PRInt16 *_retval); 
diff --git a/mozilla/widget/src/xpwidgets/nsBaseFilePicker.cpp b/mozilla/widget/src/xpwidgets/nsBaseFilePicker.cpp
index b75a53313c1..79887751a4a 100644
--- a/mozilla/widget/src/xpwidgets/nsBaseFilePicker.cpp
+++ b/mozilla/widget/src/xpwidgets/nsBaseFilePicker.cpp
@@ -162,4 +162,19 @@ nsBaseFilePicker::AppendFilters(PRInt32 aFilterMask)
   return NS_OK;
 }
 
+//-------------------------------------------------------------------------
+//
+// Set the filter index
+//
+//-------------------------------------------------------------------------
+NS_IMETHODIMP nsBaseFilePicker::GetFilterIndex(PRInt32 *aFilterIndex)
+{
+  *aFilterIndex = 0;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsBaseFilePicker::SetFilterIndex(PRInt32 aFilterIndex)
+{
+  return NS_OK;
+}
 
diff --git a/mozilla/widget/src/xpwidgets/nsBaseFilePicker.h b/mozilla/widget/src/xpwidgets/nsBaseFilePicker.h
index fd4fe77f2e1..c714440d35e 100644
--- a/mozilla/widget/src/xpwidgets/nsBaseFilePicker.h
+++ b/mozilla/widget/src/xpwidgets/nsBaseFilePicker.h
@@ -39,6 +39,8 @@ public:
                   PRInt16 aMode);
 
   NS_IMETHOD AppendFilters(PRInt32 filterMask);
+  NS_IMETHOD GetFilterIndex(PRInt32 *aFilterIndex);
+  NS_IMETHOD SetFilterIndex(PRInt32 aFilterIndex);
 
 protected: