3rd Party dll creating memory leek no dispose method for class

[Brano]

HI all

The problem is I have a 3rd party class that doesnt have a dispose
method. It has however a OpenConnection method and a CloseConnection
method but I call both of these and the class creates a memory leak. I
even set the object to Nothing afterwards but still the memory leek
appears. I have tried GC.Collect afterwards too but didnt help Here is
snippet of my code :
Dim mobjUDConn As connection '# this object is declared in 3rd party
DLL that is referenced
Dim mobjUDDB As connDatabase '# this object is declared in 3rd
party DLL that is referenced
'#SUB CONNECT
Dim ErrMsg As String
Try
If mobjUDConn Is Nothing Then
mobjUDConn = New connection
End If
If mobjUDConn.isConnected = False Then
With mobjUDConn
.Host = sHost
.Port = sPort
.User = sUser
.Password = sPassword
.Database = sDatabase
mobjUDConn.open()
End With
End If
If mobjUDDB Is Nothing Then
mobjUDDB = New connDatabase
End If
If mobjUDDB.isConnected = False Then
mobjUDDB = mobjUDConn.getDatabase
End If
ErrMsg = ""
Catch ex As Exception
ErrMsg = ex.Message
End Try

'# Thats it connection opened
'# Do reads / writes here

'##### Close Connection ####
mobjUDDB.close()
'# ##### PROBLEM HERE #######
'# Problem is here mobjUDDB doesnt have a dispose method
mobjUDConn.close()
mobjUDConn.Dispose()

mobjUDDB = Nothing
mobjUDConn = Nothing

Can anyone tell me what more can I do to kill the object mobjUDDB ???