SourceForge Project Page
jpilot-icalendar is currently a standalone program that imports RFC2445 (aka iCalendar) events into J-Pilot. TODOs are not currently supported.
The intent is to make jpilot-icalendar a full-fledged conduit, so that it will synchronize an iCalendar file with J-Pilot (and, hence, the Palm Datebook app).
jpilot-icalendar is currently an alpha release. I believe it to be safe, but as with anything else, there is always the possibility that something could go wrong. Please backup your data first if you cannot afford to lose it.