Changing Permalinks and 301 redirects

I am on 3.0.1 version of wordpress.

I want to change my permalink structure from domain.com/year/month/date/posttitle to domain.com/posttitle.

However, changing it breaks all incoming links, and I thought 3.01 would automatically redirect you.

Thought it would do it automatically because if I goto domain.com/posttitle it does redirect me to /domain.com/year/month/date/posttitle

Is there something I need to put in the .htaccess file?

Any help would be greatly appreciated.

Thank you,

Jason