Serialize an array of ints to send using KSOAP2

Question

I'm having a problem trying to send an array of ints to a .NET web service which expects an array in one of the arguments. That's at least what I understand from the API description on the web service which says this:

<dataIndexIDs>
<int>int</int>
<int>int</int> </dataIndexIDs>

So when I send a single int like below I do not get any errors and I think it works fine.

request.addProperty("dataIndexIDs", 63);

But when I try to send an array of ints:

request.addProperty("dataIndexIDs", new int[] {63, 62}); // array of ints

or a ArrayList of Integers:

ArrayList<Integer> indexes = new ArrayList<Integer>();
    indexes.add(63);
    indexes.add(62);
    request.addProperty("dataIndexIDs", indexes); // ArrayList of Integers

I get thrown a "java.lang.RuntimeException: Cannot serialize" exception. Any help please? What am I doing wrong? Thanks!