There is still an issue (even with the latest IS Tech Updates, haven't gotten around to fixing it yet) if the original Sales Order that generated the invoice has been purged, you have to jump through some hoops to get the void processed and posted but if the original Sales Order is still available, the actual void process works well and puts the items back on the original Sales Order Lines rather than create a bunch of new lines like it used to.
Besides, if you get updated to 2002.4, then you can sign up for the IS Tech Support updates and get all the other new things we have!