It must be possible to have a line cut tool in ArcPad that works similar to the one in ArcMap. The example line cut Applet that ships with ArcPad does terrible things to Geodatabases. The last time I attempted to use it, it cut every line in every layer of the Geodatabase, not just the line I was attempting to cut, it also extended the line cut right across the extent of all line work in the editable geodatabase, not just the line that was crossed by the line cutter line. When the data was checked back into ArcMap from ArcPad, much of the data refused to check in, presumably the unique ID of the newly cut lines were not updated and caused conflicts within the database.
Please, a good simple line cut tool for ArcPad would be fantastic.