...
//invoke a CompactDatabase method of a JRO object
//pass Parameters array
objJRO.GetType().InvokeMember("CompactDatabase",
System.Reflection.BindingFlags.InvokeMethod,
null,
objJRO,
oParams);
...
See more details at http://www.codeproject.com/KB/database/mdbcompact_latebind.aspx