android getRelativeTimeSpanString() bug?

using the built in getRelativeTimeSpanString() method in android DateUtil I am unable to get the "minutes ago" "days ago" etc. time elapsed response that the documentation says that I should receive, instead I get a result that just displays the actual date in a way such as "may 12 2010", not sure if this is a bug or what but Ive tried both getRelativeTimeSpanString (long time, long now, long minResolution) and getRelativeTimeSpanString (long startTime), both just return the actual date of the variable "long time"

here is my code

private void setJoineddate() {
    Date currentDate = new Date();
    long currentDateLong = currentDate.getTime();
    long oldDate = join_date.getTime();

    CharSequence relativeTime = DateUtils
                         .getRelativeTimeSpanString(oldDate, currentDateLong, 0);
    joindate.setText(relativeTime);

}