Client_Text_IO and errors WUC-12, WUC-14

Question

I have some pretty basic code as shown below. I just want to pull records from a cursor and output them to a .xls file. However, when I run this code, after 10 seconds or so I get the following errors:
WUC-14 [getFromObjectCache] Object Cache Error: Specified object handle -1 not found in the cache
WUC-14 [getFromObjectCache] Object Cache Error: Specified object handle -1 not found in the cache
WUC-12 [FileFunctions.putf()] Object Cache Error: Object is not the expected BufferedWriter type
The cursor is fine, this code worked fine in the past (6i) until we recently tried upgrading to the web and changed Text_IO to Client_Text_IO. The output should be 3 columns of data and about 25,000 rows. However, since I added the Client_Text_IO's I only get around 6000 rows of data before I get the errors. Also, it seems like I'm getting the last 6000 rows, the first 19,000 rows of data and the header row never get written to the file. Has anyone seen these errors before? Is there any kind of timeout setting in the config files I need to worry about? Note that all our other webutil stuff and Client_Text_IO's work fine.
-- Code --
file_handle := Client_Text_IO.FOpen( file_name, 'w' );
Client_Text_IO.PutF( file_handle,'%s \n', 'Header Text' );
for one_rec in data_cursor loop
-- the columns are tab seperated
Client_Text_IO.PutF( file_handle, '%s \n', one_rec.Item_Name || '     ' || one_rec.Item_Number || '     ' || one_rec.Test_Name );
end loop;
Client_Text_IO.FClose( file_handle );

Answer 1

Sure, here is the code. Since I posted before, I tried a few other reports we have that output over 200k of data... when I did, some of the other reports gave me the same error message.
procedure Gen_Test_Rpt is
cursor data_cursor is
select cd.item_name, cd.item_number, cd.test_name
from compact_data cd
order by cd.item_name;
file_handle Client_Text_IO.File_Type;
File_Name varchar2(1000) := 'c:\test_report.xls';
-- there are tabs between "Item Name" and "Item #" and "Item #" and "Test Name"
Header varchar2(400) := 'Item Name     Item #     Test Name';
begin
file_handle := Client_Text_IO.FOpen( File_Name, 'w' );
Client_Text_IO.PutF( file_handle,'%s \n', Header );
for one_rec in data_cursor loop
-- tab seperated
Client_Text_IO.PutF( file_handle,'%s \n', one_rec.item_name || '     ' || to_char(one_rec.item_number) || '     ' || one_rec.test_name );
end loop;
Client_Text_IO.FClose( file_handle );
end;