blog migration, need help with 301 redirect / permalinks

Hello all,

Due to security and management overhead I have consolidated my old blog at metablog.info into another existing blog at haibane.info. I want to setup an automatic rule for redirecting all old posts from the old domain to the new, but my permalink structure on the two blogs is different and I wanted to solicit some opinion on whether those differences are insurmountable.

the old blog had the permalink structure:

http://www.metablog.us/%5BCATEGORY%5D/%5BPOST-SLUG%5D/

whereas the new blog has permalink structure:

http://www.haibane.info/%5BYEAR%5D/%5BMONTH%5D/%5BDAY%5D/%5BPOST-SLUG%5D/

examples:
OLD: http://www.metablog.us/blogging/ahp-recent-posts-plugin-for-wordpress-mu/
NEW: http://www.haibane.info/2008/09/17/ahp-recent-posts-plugin-for-wordpress-mu/

I have a sinking feeling that the date information in the new permalink format will be hard to auto-generate, if not impossible, since that is new information in the URL which does not exist in the old one.

Frankly, if theres no magical apache rule that will do the job, then i’m fine with solely redirecting the specific two posts above using hardcoded URLS, and then writing more general redirects such as :

OLD: http://www.metablog.us/%5BCATEGORY%5D/%5BPOST-SLUG%5D/
NEW: http://www.haibane.info/tag/%5BCATEGORY%5D

(I can easily map the old categories on the old blog to categories on the new one). This will basically redirect the user not to the exact post, but hopefully a list of related posts including the one they were after.

My problem is I’ve never edited htaccess before and to be honest I dont even want to run wordpress on the old domain (will just have an static page there advising of the blog migration,and eventually let the domain lapse once Google has digested the 301s).

So, can someone help me out with this? Is my ideal redirect possible? If not, how would you do the next best scenario above? help! thanks 🙂

Regards
Aziz