SSIS And OLE Automation

In MSS 2000, it was possible to have a stored procedure that used OLE Automation to execute a DTS package. E.g.

declare @oPKG int

exec sp_OACreate 'DTS.Package', @oPKG OUTPUT

declare @pkgName varchar(128)

declare @server varchar(20)

declare @cmd varchar(1100)

declare @userid varchar(20)

declare @ServerPWD varchar(20)

set @pkgName = 'PKTestOuter'

set @Server='myServer'

set @userid='myuser'

set @ServerPWD='myPW'

SET @Cmd = 'LoadFromSQLServer("' + @Server +'", "' + @userid + '", "' + @ServerPWD + '", 0, , , , "' + @PkgName + '")'

EXEC sp_OAMethod @oPKG, @Cmd,NULL

exec sp_OAMethod @oPKG, 'Execute'

When I move - but not migrate - packages to 2005, this still works. I don't have a problem with permissions or any of the other problems that I have seen posted in this forum. But if I migrate a package to SSIS, the package is now seen in sysdtspackages90 instead of table sysdtspackages (assuming I remove the old version). But "LoadFromSQLServer(...)" can't find it anymore. So it seems like one of the following is true:

a) There is a different item that I should use in sp_oacreate besides DTS.Package. I tried SSIS.Package or DTS.Package90 which seemed like reasonable possibilities but they don't work. Is there something that will work? Or is "LoadFromSQLServer(...)" not supported for SSIS packages?

b) Or OLE Automation doesn't work with SSIS packages. OLE Automation is enabled and it works on non-migrated packages. Is it true that it was decided by Microsoft that this capability was not needed in SSIS?

I see numerous postings saying not to use the sp_OA routines. I understand there are other ways to execute an SSIS package from a SP and that there may be more secure ways. But I need to know if it is an absolute requirement to use these other methods.

Paul