Anagrams of a word (Including same letters case)

Question

I have a word "ab", and I want to print all possible cases of those letters:

"aa"
"ab"
"ba"
"bb"

There is a function to do this:

function generateAnagrams(word, number) {

        if (word.length < 2) {

            return [word];

        } else {

            // By declaring all variables outside of the loop,
            // we improve efficiency, avoiding the needless
            // declarations each time.

            var anagrams = [];
            var before, focus, after;
            var shortWord, subAnagrams, newEntry;

            for (var i = 0; i < word.length; i++) {

                before = word.slice(0, i);
                focus = word[i];
                after = word.slice(i + 1, word.length + 1);
                shortWord = before + after;
                subAnagrams = generateAnagrams(shortWord, number);

                for (var j = 0; j < subAnagrams.length; j++) {

                    newEntry = focus + subAnagrams[j];
                    newEntry = newEntry.substr(0, number);
                    anagrams.push(newEntry);

                }

            }
            //Remove all duplicate letters from array
            //This prevent substr above from generate
            anagrams = unique(anagrams);
            return anagrams;

        }

    }

    function unique(list) {
        var result = [];
        $.each(list, function (i, e) {
            if ($.inArray(e, result) == -1) result.push(e);
        });
        return result;
    }

//"ab" is inputed word
//2 is number of characters for each case
generateAnagrams("ab", 2);

From example code above, it give me a result of only two cases "ab" and "ba". Thus I want your help to modify the code to get the result that I want above.

JSFiddle: http://jsfiddle.net/LfL6sea3/

Extra explanation: For the suggestion of @Dekel, I think it is not really answer my question. My question is to get all possible case of the letters from a word. Look at an example below:

If I have a word "ab" then all possible case of two letters are: aa,ab,ba,bb.

If I have a word "abc" then all possible case of three letters are: aaa,bbb,aab,bba,aba, ccc,cbc,cac,acc,bcc,ccb,cca,bab,abc,acb,bac,bca,cab,cba.