Where can I find information on how to customize the user registration process of Liferay + Sun Web Space Portal

I need to quickly customize the user registration form of the liferay/web space portal? Have not found any direct information on this so would appreciate any tips.

There are several possibilities:

• The source is available, so you might want to patch the existing process
• The API is available (e.g. see this thread in the liferay forum), so you can batch-create users or implement your own registration portlet and just use the API. AFAIK you can even register users via a webservice interface.
• You can batch-insert users into the database
• If your existing user data is stored in LDAP, you can connect Liferay to the database.