query from a list of ids

Hi,

Here is my first table:

Table1

name| ids
-------------------------
Peter| 2, 3, 4, 5
Jack| 100, 34, 3

Both name and ids are in text format.

Here is my second table

Table2

id | Flag | Title
---------------------
2 | Red | good
3 | Blue | poor
4 | Green| middle

id is in integer (serial) format.

I would like to list all the rows in table 2 where the id is in the
ids field of peter. So I did

select * from tables where id in (select ids from table1 where
name='Peter')

It did not work. How can I do the query?

Thanks,

ff