vTiger - import leads and events at the same time

Pay attention: this project is for developers which have strong skills on vTiger customization. VTiger 5.04 allows to import separately ACCOUNTS, LEADS and CONTACTS by .csv files. Is not allowed to import events data (calls or meetings information regarding account, lead or contact). I have an excel file that contains leads data and events data (info regarding sales appointment with each lead). All in one file. I need to customize vTiger to have a button to import all those information (LEADS and relatives MEETINGS data).