questions on drop down list

Hello all!!im filling a dropdown list with results from a query as the code shows (i fill the drop down everytime i open the xls file), BUT this dropdown keeps all information when i close the file and when i run the code again the result is merged into the older, i need to clean the dropdown in this code before i fill it again!!! i tried .Clear but excel says it doesnt belong to the object class..i dunno what to do

Sub Auto_Open()

Const strActiveConnection = "DSN=TURMALINA;Description=TURMALINA;;;APP=Microsoft Office 2003;WSID=GENERATOR;DATABASE=JDE_DEVELOPMENT;Network=DBMS"

Const strSQL = "SELECT " & _
"prj = CONVERT(VARCHAR(4),F58009.IMPRJCOD) + '-' + CONVERT(VARCHAR(4),F58009.IMSEQ) + ' - ' + LTRIM(RTRIM(F58001.PDDSCA))+ ' - ' + LTRIM(RTRIM(F58009.IMDSCA)), " & _
" prj2 = CONVERT(VARCHAR(4),F58009.IMPRJCOD) + '-' + CONVERT(VARCHAR(4),F58009.IMSEQ) " & _
" FROM JDE_DEVELOPMENT.TESTDTA.F58009 F58009, " & _
" JDE_DEVELOPMENT.TESTDTA.F58001 F58001 " & _
" WHERE F58001.PDPRJCOD = F58009.IMPRJCOD"


Dim cnx1 As Object
Dim rst1 As Object

Set cnx1 = CreateObject("ADODB.Connection")
Set rst1 = CreateObject("ADODB.Recordset")
cnx1.Open strActiveConnection
rst1.Open strSQL, cnx1
Set ExecuteSQL = rst1


Dim Count As Integer
Count = 0


Do While Not rst1.EOF
ActiveSheet.Shapes("Drop-Down 10").Select
With Selection
.AddItem rst1("prj")
End With
Count = Count + 1
ReDim Preserve ArrayAux(1 To Count)
ArrayAux(Count) = rst1("prj2")
rst1.MoveNext
Loop
rst1.Close
Set rst1 = Nothing


End Sub

someone to help me please?

i also need to know whats the macro name when the user select something in the drop down list.




Thank You,
tyagi