NetBeans IDE 4.2 [200504101800] on jdk 1.5.0_03

1, Have this code:
        HashMap hmap = new HashMap();
        for (int i=0; i<10; i++) {
            hmap.put(""+i, i+".item");
        }
2, Stop on breakpoint after this code
3, Create watch hmap.put("6", "test") => the watch is sometimes eavaluated only
once (i.e. the value is "6.item") and sometimes it is evaluated more times (i.e.
the value is "test")