Anagram Mode in Word

Anyone knows why I get the error THE SPELLER DOES NOT SUPPORT ANAGRAM MODE when using wdAnagram mode for GetSpellingSuggestions?

I'm using Microsoft Office 2000's Visual Basic Editor. Here's the code:

VB Code:

Function GetAnagrams(sSpelledWord As String) As SpellingSuggestions
    Set GetAnagrams = Word.GetSpellingSuggestions(sSpelledWord, SuggestionMode:=wdAnagram)
End Function