Problem calling an external DLL from VB.Net 2003

[Michael]

Trying to call an external DLL (compiled within Fortran) and keep on getting
the following error in the main call to the external DLL

' Object reference not set to instance of object'

The DLL import definition is located within its own class as follows:
'
'
Imports System.Runtime.InteropServices
'
Public Class LAPACK
'...
<DllImport("C:\G95\_LAPACK\DGGEV_DLL\dggev.dll", EntryPoint:="dggev_",
SetLastError:=True, _
CharSet:=CharSet.Unicode, ExactSpelling:=True, _
CallingConvention:=CallingConvention.StdCall)_
Public Shared Sub _
DGGEV(ByVal JOBVL As Char, ByVal JOBVR As Char, ByVal N As Integer, _
ByRef A(,) As Double, ByVal LDA As Integer, ByRef B(,) As Double, _
ByVal LDB As Integer, ByRef ALPHAR() As Double, ByRef ALPHAI() As
Double, _
ByRef BETA() As Double, ByRef VL(,) As Double, ByVal LDVL As Integer, _
ByRef VR(,) As Double, ByVal LDVR As Integer, ByRef WORK() As Double, _
ByVal LWORK As Integer, ByRef INFO As Integer)
End Sub
'
End Class
The main net program calls the procedure as follows

Call LAPACK.DGGEV("N", "V", N, S, LDA, T, LDA, ALPHR1, ALPHI1, _
BETA1, Q, LDQ, QE, LDQE, WORK, LWORK, IERR)

As soon as the call occurs the error message appears.

Any ideas would be appreciated

Mike C.