Código Delphi [-]
//mi codigo:
 with frmdata do
       begin
         sp_sql.ProcedureName:='SP_guarda_tipo_persona';
         sp_sql.Parameters.ParamByName('@desc_tipo').Value:=FrmTiposPersona.desc_tipo_edit.Text;
         sp_sql.Prepared:= True;
         try
           if not conexion.InTransaction=true then conexion.BeginTrans;
           sp_sql.ExecProc;
           conexion.CommitTrans;
         except
           conexion.RollbackTrans;
         end;
       end;

//Error que da:
---------------------------
Debugger Exception Notification
---------------------------
Project Simotesis.exe raised exception class EDatabaseError with message 'sp_sql: Parameter '@desc_tipo' not found'.
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Break   Continue   Help   
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Código Delphi [-]
--a este store procedure es que estoy haciendo llamada.
USE [db_simotesis]
GO
/****** Object:  StoredProcedure [dbo].[SP_guarda_tipo_persona]    Script Date: 12/02/2011 17:50:47 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author:  Miguel Garcia
-- Create date: 28/11/2011
-- Description:  Guarda Tipo Persona
-- =============================================
Create Procedure SP_guarda_tipo_persona
  -- Add the parameters for the stored procedure here
    @desc_tipo varchar(50)
AS
BEGIN
  -- SET NOCOUNT ON added to prevent extra result sets from
  -- interfering with SELECT statements.
  SET NOCOUNT ON;

    -- Insert statements for procedure here
  insert into tb_tipo_persona_m (descripcion_tipo)values(@desc_tipo)
END

Código SQL [-]
Create Procedure SP_guarda_tipo_persona (@desc_tipo varchar(50))