We actually resolved this issue a while ago in the open source JIDE Common Layer. There is a comparator called AlphanumComparator under jidesoft.comparator package. (courtesy to David Koelle). As long as you use this comparator, it will sort the strings with numbers correctly according to what users would expect. See below. The list on the left is the straight alphabetic sorting. The list on the right is using the alphanum sorting.

If you are using SortableComboBoxModel or SortableListModel, you can simply call the code below to enable the alphanum sorting.

  sortableComboBoxModel.setComparatorContext(AlphanumComparator.CONTEXT);

and

  sortableListModel.setComparatorContext(AlphanumComparator.CONTEXT);