how can I delete double values in mysql?

[Anon]

Scenario:

Let's say I have one table with like 2000 entries. Each entry consists of 4 fields.
Each entry or row of course has a unique id and I have entries which contain the same values in a field and I want to delete these.
How do I do this?

Example:

Fields: id, name, email, homepage

Row1: 1, jack, [e-mail], http://www.jack.com

Row2: 2, laura, [e-mail], http://www.laura.com

Row3: 0, 0, 0, http://www.jack.com

How can I delete Row3 but keep Row1? Row3 has the same homepage value as Row1.

Thanks for any help.

[Anon]

Oops, I made a mistake.

Row3 of course has id = 3 and not = 0