Schema accidentaly dropped in pg_namespace table

Hi all,

I've dropped a schema in my database with this command :

delete from pg_namespace where nspname = "toto";

I know ... I 've done a big mistake :( . I will prefer "drop schema
toto" the next time.

Now I can't do a pg_dump because some objects of the removed schema are
still referenced in pg_* tables. pg_dump does not know what to do in
this case and returns an error message.

My questions are the following :
- Is there a cleaning tool that allow me to find and delete objects that
references the removed schema ?
- Is there a document that graphically shows the postgresql internal
tables model ?
- Any other ideas ... ?

Thanks by advance,

Benoit