Are you hitting the now enforced length restriction of Textareas in your existing applications after upgrading to APEX 4.2? Then you should read Joels blog posting APEX 4.2 and Textareas for additional information and a fix.
If you want to make your applications future prove then I would suggest that you run the following query in SQL Workshop. It will return you all the textareas which are bound to a database column and where the length specified for the textarea doesn’t match with the database column length definition.
select i.application_id, i.page_id, i.item_name, i.item_element_max_length, c.data_type, case when c.data_type = 'CLOB' then 32767 else c.data_length end as data_length from apex_application_page_items i, apex_application_page_proc p, user_tab_columns c where i.display_as_code = 'NATIVE_TEXTAREA' and i.item_source_type = 'Database Column' and p.application_id = i.application_id and p.page_id = i.page_id and p.process_type_code = 'DML_FETCH_ROW' and c.table_name = to_char(regexp_replace(p.process_source, '^[^:]*:([^:]*).*', '\1')) and c.column_name = i.item_source and ( ( c.data_type = 'CLOB' and i.item_element_max_length < 30000 ) or ( c.data_type = 'VARCHAR2' and c.data_length > i.item_element_max_length ) ) order by 1, 2, 3;
Note: This query assumes that your workspace is only assigned to one database schema! If you have multiple schemas assigned, you have to change the “Schema” select list in SQL Commands and run the statement for each schema you find there.