It seems to take journal, ditemid, parenttalkid, poster, body, subject and props.
ditemid is self-explanatory, but I'm not sure what parenttalkid is. Every time I've tried to call the method, I get an error of 'No such entry. at /home/lj/cgi-bin/ljprotocol.pl line 250'. Looking at the code, this is right after the journal specified by the journal argument is pulled from the table. Any ideas?