My Software has an option to archive older data to an read-only
marked database which may be stored to a CD or DVD. I created a
Viewer program using IBObjects that displays the data. That worked
very well up to Firebird 2.0.3.

Now I moved to Firebird 2.1.1. On opening a query with TIBOQuery
(IBObjects) I get following error message:

attempted update on read-only database.

I debugged the source code of IBObjects and found out that following
statement is used before opening the Query:

SELECT F.RDB$FIELD_NAME F_FieldName
, F.RDB$RELATION_NAME F_RelationName
, F.RDB$DEFAULT_SOURCE F_DefaultSource
, D.RDB$DEFAULT_SOURCE D_DefaultSource
, D.RDB$FIELD_TYPE D_FieldType
FROM RDB$RELATION_FIELDS F INNER JOIN RDB$FIELDS D
ON D.RDB$FIELD_NAME = F.RDB$FIELD_SOURCE
WHERE (( F.RDB$DEFAULT_SOURCE IS NOT NULL ) OR ( D.RDB$DEFAULT_SOURCE
IS NOT NULL ))
AND NOT F.RDB$RELATION_NAME STARTING WITH 'RDB$'
ORDER BY 1

I tried some combinitians and found out that follwing statement fails
with that error message:

select *
from rdb$relation_fields
where rdb$default_source is not null

The problem seems to be, that I created some columns with default
values. I did a workaround for my archive database an elliminate
every "default x" from the "create table" statements. Now everything
works fine again.

Maybe somebody else have the same problem and knows now what to do,
or Jason reads this (Hi Jason... :-)) and he creates a workaround in
the next version of IBObjects.

I made a bugtracker item at Firebirdsql.org too, but this issue can't
be reproduced at isql and so it might not be changed.