Security settings

I've managed to mess up the permissions on all of the tables in one of my databases.... One way or another. I'm not sure of the actual sequence of events, but I think that a user of the database got deleted, while it was set as having privileges on these tables. Ever since then, things have been not quite right.

When I try to open the properties pane in pgadmin 2, I get the following error:

-- Error Information --

Description: Element not found
Number: 35601
Routine: pgAdmin II:frmTable.Initialise

And then I can continue, but it doesn't show me any of the assigned security info for the table.

At the command line, here are the permissions:
plesionym-# \dp
Access privileges for database "plesionym"
Schema | Table | Access privileges
--------+-------------------------------+-------------------
public | mtstb_plesmnt_context | {=,mirpub=r}
public | mtstb_plesmnt_edit_session | {=,mirpub=r}
public | mtstb_plesmnt_phrase | {=,mirpub=r}
public | mtstb_plesmnt_phrase_relation | {=,mirpub=r}
public | mtstb_plesmnt_phrase_type | {=,mirpub=r}
public | mtstb_plesmnt_source | {=,mirpub=r}

If I try to do the same thing in pgadmin 3 I don't get any errors, and it shows me the proper security. However, I do get an error here if I try to change any of the security settings. I get
"ERROR: parser: parser error at or near "ALL" at character 58"

Can someone give me an idea of how to fix this?

Thanks,

Dan