Constraint Error

["Rick Santa-Cruz" <rick_santa_cruz75@msn.com>]

Hi,

how can I avoid the Constraint Error, when executing the following code:

with Messages;

procedure Test_Messages is
 M1: Messages.Message;
 M2: Messages.Message;

begin
 m1:=Messages.Create("This is a test");
 m2:=Messages.Create("This is a second test");
end Test_Messages;
----------------------------
 package Messages is
 type Message is tagged private;
 subtype String_Txt is String(1..20);

 function Create(Str: String) return Message;

 private
  type Message is tagged
   record
    Text: String_Txt;
   end record;
end Messages;
------------------------------
package body Messages is
 function Create(Str: String) return Message is
  M: Message;
 begin
  M.Text := Str;
  return M;
 end Create;
end Messages;

The Constraint Error occurs in the Create-Function.

Thanks in advance,
Rick