Running child package from script task on windows 2008 server

Scenario: We have an SSIS package which has a script task. This script task has a package.Execute() statement which runs another package.

This child package has an 'Execute Process task' which calls an .exe

Both these packages are built using ssis in visual studio 2005. And the parent package was scheduled to run on a Windows 2003 server.

Problem: Now, we have to migrate this job to windows 2008 server. I got SSIS 2005 installed on this system and gave an explicit path to call the package:

"C:\Program Files (x86)\Microsoft SQL Server\90\DTS\Binn\DTExec.exe" /f "\\ustca974\Share\KC-HC\PRINCE\QA\Scheduler_Package.dtsx" /MAXCONCURRENT " -1 " /CHECKPOINTING OFF  /REPORTING V

The script inside the package is like:

Private Sub StartTask()
    Dim _errorMsg As System.Text.StringBuilder = New System.Text.StringBuilder("")
    Dim str_To As String
    Dim str_From As String
    Dim str_Message As String
    Dim str_Subject As String
    Dim isSimulationComplete As Boolean = False

    Try
        Dim app As Application = New Application()
        Dim _PackageVars As Variables = Nothing
        Dim _PackagePath As String = System.IO.Path.Combine(Dts.Variables("User::ExecutionPath").Value.ToString, _
            Dts.Variables("User::PkgName").Value.ToString)
        Dim pck As Package = app.LoadPackage(_PackagePath, Nothing)
        _PackagePath = _PackagePath.Replace(System.IO.Path.GetExtension(_PackagePath), ".dtsConfig")
        If (pck.Configurations.Count > 0) Then
            If System.IO.File.Exists(_PackagePath) Then
                pck.Configurations(0).ConfigurationString = _PackagePath
                pck.ImportConfigurationFile(pck.Configurations(0).ConfigurationString)
            End If
        End If

        pck.VariableDispenser.GetVariables(_PackageVars)
        For Each var As Variable In pck.Variables
            If (Not var.SystemVariable) And Dts.Variables.Contains(var.QualifiedName) Then
                pck.VariableDispenser.LockForWrite(var.QualifiedName)
                var.Value = Dts.Variables(var.QualifiedName).Value
            End If
        Next
        If (_PackageVars.Locked) Then

            _PackageVars.Unlock()
        End If
        UpdateRequestsStatus("3")
        pck.Execute()
        For Each errorObj As DtsError In pck.Errors
            _errorMsg.AppendLine("Source: " & errorObj.Source & vbNewLine & "Desc: " & errorObj.Description)
        Next
        Dts.TaskResult = pck.ExecutionResult

after migration, the job goes long running at the pck.Execute() statement. It does not throw any error. I tried on my local machine access the package on that server and it works fine. I dont have administrator access on that server so cannot run it there. I feel there is some framework or setup issue. Some thing is missing being installed. But not sure what exactly. Does anyone have any idea? Thanks a lot for the help