The best method and for future proofing (so next time it is as easy as possible) is to sync your Ericson with Outlook or other app, export the contacts from Outlook to a CSV file, upload that to a gmail or google apps account and then enable google sync on yoru iPhone.
This way all you have to do on yoru iPhone (or any other smart phone that supports active sync) is to enter a username and password and it pulls down all your contacts. Any changes you make on your handset are then added to your contacts on gmail and should you lose or change phone all your contacts are niceley backed up and can be pulled down to you new handset with ease.