Hi, I would like to know what is wrong, I get this error message
ISC ERROR CODE 335544831
ISC EROR MESSAGE:
please retry, specifying an option

when submiting this sentence
SELECT
F_CHAVESORT(C.CCT_ORD, C.CCT_CONT, C.CCT_CONT, C.CCT_TIT) AS TEST
FROM CONT C

F_CHAVESORT was declared this way:
DECLARE EXTERNAL FUNCTION F_ChaveSort
INTEGER, CSTRING(24), CSTRING(24), CSTRING(60), CSTRING(90)
RETURNS PARAMETER 5
ENTRY_POINT 'ChaveSort' MODULE_NAME 'rsf_udf';

This is Delphi 7 related code:

library rsf_udf;
uses
SysUtils,
Classes,
RSFuncs in 'RSFuncs.pas';
{$R *.res}
begin
end.

unit RSFuncs;
interface
uses
SysUtils, StrUtils, ibase, ib_externals;

function ChaveSort(Ordem: Integer; Conta, ContaMae, Titulo, Chave:
PChar): PChar; cdecl; export;

implementation

function ChaveSort(Ordem: Integer; Conta, ContaMae, Titulo, Chave:
PChar): PChar;
begin
result := Chave;
if (Ordem < 0) then
Chave := PChar(ContaMae + StringOfChar(' ', 6) + Titulo)
else
Chave := PChar(ContaMae + Format('%6.6u', [Ordem]) +
RightStr(Conta, (Length(Conta) - Length
(ContaMae))));
end;

end.