The GroupWise client has a lot of cool features, but sometimes it just doesn't do that one little thing that you need it to do. The GroupWise "Threaded" display view is very handy at sorting messages in hierarchical fashion, showing who replied to which message, etc. However, GroupWise relies on internal "thread ID" properties to provide this view. These thread ID properties are often not maintained when messages leave the GroupWise system, or come in from Internet senders. Thus, the Threaded View doesn't do a good job of properly sorting messages from Internet mail lists. Sorting by the subject doesn't help either, as the original message to a mailing list and all of the replies typically have different subjects (the replies all have "Re:" prepended to the subject).
The GW Thread Sorter is an Advansys Formativ applet that solves this problem by reducing a folder view to just those messages that have the original subject in the subject field (minus any "Re:" additions). With the click of a button, you can quickly see all Internet mail list messages that are related to the same subject, including the original message and all of it's replies.