[Mono-list] is inaccessible due to its protection level (CS0122). possible Bug?

[DW]

Hello,
i get the compile error if i try to run my app from Sharpdevelop on my Windows Box. MS compiler isn't complaining.
on my Linux Testing box a different mono Version is running the app without problems.

Here are my version.

//Windows
Mono JIT compiler version 1.2.3.1, (C) 2002-2006 Novell, Inc and Contributors. www.mono-project.com
        TLS:           normal
        GC:            Included Boehm (with typed GC)
        SIGSEGV:       normal
        Architecture:  x86
        Disabled:      none
        
//Linux
Mono JIT compiler version 1.2.2.1, (C) 2002-2006 Novell, Inc and Contributors. www.mono-project.com
        TLS:           normal
        GC:            Included Boehm (with typed GC)
        SIGSEGV:       normal
        Disabled:      none        


the compiler is complaining about Result of Search.Result

public Download(Search.Result result)
{
  //CODE
  ...
}

here's the class:

partial class Search
{
  public sealed partial class Result
  {
    //CODE
    ...
  }
}