Thank you for replying:
here is the simplified part of the code
'-------------------------------------------------::::
Imports System
Imports System.Text.RegularExpressions
Imports Microsoft.VisualBasic
Imports Microsoft.Win32
Imports System.Text.Encoding

<ComClass(IeStringClass.ClassId, IeStringClass.InterfaceId,
IeStringClass.EventsId)> _
Public Class IeStringClass

#Region "COM GUIDs"
   ' These  GUIDs provide the COM identity for this class
   ' and its COM interfaces. If you change them, existing
   ' clients will no longer be able to access the class.
   Public Const ClassId As String = "0a487659-4f71-45f5-b4cd-223d897c40ba"
   Public Const InterfaceId As String =
"a0654bfb-dca9-4f3b-82ab-62e77e11d08a"
   Public Const EventsId As String = "194cb6e2-0e1f-46bb-9fac-0eb312219681"
#End Region

'  ... some constant declarationa nd soem class variables
   Dim Date_Patterns() As String
' ...

   Public Sub New()
       '050917 fixed patterns by adding ignorecase
       MyBase.New()
 '.... some initialztion code
 '   buildup up string values into Date_Patterns
End Sub

    Public Function getDate_Patterns() As String()  ' does not work: Type
Mismatched
       Return Date_Patterns
   End Function

   Public Function getDate_PatternsSz() As Integer   ' tested
       Return Date_Patterns.GetUpperBound(0)
   End Function

   Public Function getDate_PatternsElement(ByVal i As Integer) As String
' tested
       If i <= Date_Patterns.GetUpperBound(0) Then
           Return Date_Patterns(i)
       Else
           Return ""
       End If
   End Function

....

   Public Function atst(ByVal iCnt As Integer, ByRef iarr As Integer()) As
Integer() ' again call to this funciton results in "type mismatch or invalid
call"
       'Public Function atst(ByVal iCnt As Integer, ByRef astr As
Collection) As Integer
       ' Dim lstrA() As String = {"a", "b", "c", "d", "e"}
       Dim lstrA() As Integer = {1, 2, 3, 4, 5}
       iarr = lstrA.Clone()
       If iCnt > 5 Then
           iCnt = 5
           atst = lstrA.Clone()
       ElseIf iCnt > 0 And iCnt <> 5 Then
           ReDim Preserve lstrA(iCnt)
           atst = lstrA.Clone()
       Else
           iCnt = 0
       End If

   End Function

End Class\
' ------------------ End of code ------------