C# and Linux shared libraries

[JacekPlacek]

Hello.
I need any sample how to invoke Linux dlopen() from c# ( mono ).
With following construction:
*******************************************
[DllImport("dl", CharSet=CharSet.Auto)]
private static extern IntPtr dlopen(string lpFileName, int flags);

[DllImport("dl")]

public static extern string dlerror();

IntPtr hModule = dlopen("/usr/lib/libaetpkss.so.2", 1);
if (hModule == IntPtr.Zero)
{
System.Console.WriteLine( dlerror() );
}
********************************************

I still get hModule = 0 and dlerror() reports "dlopen: invalid caller"

What is wrong in my code ?

Best regards
Jacek