vb2010好奇怪的问题，子窗体调dll函数报错

vb调用一个VC6写的的dll，VB6怎么调用都没问题
VB2010需要把所有long类型全转化为integer类型才行(这只是在启动主窗体中调用dll中的函数)
如果在mdi子窗体中调用dll中的函数则会报这个错误：


我所有的dll中的函数都是已经在模块中声明好了的

'结构声明：

    Public Structure CapInfoStruct

        Dim Buffer As Integer

        Dim Height As Integer

        Dim Width As Integer

        Dim OffsetX As Integer

        Dim OffsetY As Integer

        Dim Exposure As Integer



        Dim Gain() As Byte

        Dim Control As Byte

        Dim InternalUse As Byte

        Dim ColorOff() As Byte

        Dim Reserved() As Byte

    End Structure





'函数声明：

    Public Declare Function HqDLSetCapInfo Lib "HQDLAPI.dll" (ByRef hCamera As Integer, ByRef pCapInfo As CapInfoStruct) As Integer

    

    Public m_hDevice As Long '这里的long不能改为integer,改之后在启动窗体中调用都会报上面错误

    Public m_CapInfo As CapInfoStruct





'调用：

    HqDLSetCapInfo(m_hDevice, m_CapInfo)