I have the following callback signature and the delegate I am using for
the function pointer:

//C++ Callback Signature:
void(*pErrorHandler)(acTErrorMsgType ErrorMsgType, acTErrorCode
ErrorCode, acTBoardHandle BoardHandle, acTChannelHandle ChannelHandle,
const char *Format, ...);

//C# delegate for callback:
public delegate void ErrorHandlerDelegate(
ErrorMsgType errorMsgType,
ErrorCode errorCode,
int boardHandle,
int channelHandle,
string errorString);

Is there a way to marshall the C++ '...' variable parameter list from
C#, perhaps using a Param Array (..., params object[] args)?