two step registration?

[trip008]

our registartion form has a lot of fields for the user to fill out and i get the feeling that a lot of users give up instead of fully registering. is there any way of having registration be a two step process where:

first, the user fills out a very short page (just username/pass/email)

once they submit, they are notified that they will receive an activation email, and taken to a second page where they fill in the rest of the profile fields.

is there a hack like this?