dynamic Stored procedure using pivot in sql server2005

This stored procedure I written to convert Semester as column
set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
go
ALTER PROCEDURE [dbo].[StudentSemesterMarks]
@Section_Id int,
@sessionid int

--Surabhi
AS
Declare @dta Varchar(500)
Declare @drt Varchar(1000)
Declare @rt varchar(10)
Declare @cnt int
Declare @daver Varchar(500)
BEGIN
DECLARE @test1 CURSOR
SET @test1 = CURSOR FOR SELECT DISTINCT Semester_Id
FROM L_Student_Semester_Marks_Detail



Select @cnt= Count(distinct Semester_Id) FROM L_Student_Semester_Marks_Detail
Set @dta = ''
Set @drt = ''




OPEN @test1
FETCH NEXT FROM @test1
INTO @rt
print @rt
WHILE @@FETCH_STATUS = 0
BEGIN
Set @dta = @dta + '['+ rtrim(@rt) +'],'
Set @drt = @drt + '+ CASE WHEN ['+ rtrim(@rt) +'] IS NULL THEN 0 ELSE ['+ rtrim(@rt) +'] END '
FETCH NEXT FROM @test1
INTO @rt
END
CLOSE @test1
DEALLOCATE @test1
--Set @dta = '[EAS-101],[EAS-102],[EAS-103],[EEC-101],[EEE-101],[EME-101] '
SET @dta= Substring(@dta,0,Len(@dta))
SET @drt= Substring(lTrim(rTrim(@drt)),2,Len(lTrim(rTrim(@drt))))
print @dta
print @drt

exec ( 'select Student_ID, University_RollNo,Student_Name,Father_Name,Date_of_Birth,Phone,LOCAL_ADDRESS,HPercent,iPercent,BPercent,' + @dta + ',' + @drt + ' as Average
from
(
SELECT * FROM L_Student_Semester_Marks_Detail INNER JOIN
V_2010_Section_StudentO ON L_Student_Semester_Marks_Detail.Student_Id = V_2010_Section_StudentO.Student_Id
WHERE Section_Id = ' + @Section_id + ' AND SESSION_ID= ' + @sessionid + '
) ps
pivot
(
Sum(Marks) for Semester_id in (' + @dta + ')
) as pvt'
)
END