import type library cdosys.dll error

When I import type library from cdosys.dll(in Windows2000), Delphi5 generate
a CDO_TLB.pas for me.
But it lost some constant definition like cdoSmtpServer,....

I use OleView to open the cdosys.dll, and find the following IDL definition

    // NOTE: This module has no entry points and thus is invalid.
    //       There is no way to extract the dllname of a module
    //       with no entry points
    //
    [
      dllname("<invalid typelib>")
    ]
    module CdoConfiguration {
        [entry(00000000)const BSTR cdoAutoPromoteBodyParts =
"http://schemas.microsoft.com/cdo/configuration/autopromotebodyparts";
        [entry(0x00000001)const BSTR cdoFlushBuffersOnWrite =
"http://schemas.microsoft.com/cdo/configuration/flushbuffersonwrite";
        [entry(0x00000002)const BSTR cdoHTTPCookies =
"http://schemas.microsoft.com/cdo/configuration/httpcookies";
        [entry(0x00000003)const BSTR cdoLanguageCode =
"http://schemas.microsoft.com/cdo/configuration/languagecode";
......

It seems, there are something wrong in cdosys.dll. But I can use it's type
library(all the constants)  in VisualBasic.

Is it a Delphi5's bug? Or, How can I figure out this problem?

Thanks

Steve Liu