[Mono-osx] managed c# call to unmanaged c++

[dman at nycap.rr.com]

Hello 
I am trying to call unmanaged code from managed c# code by using p/invoke. 

I have the following dllimport attribute in my managed DLL 

[dllimport("UnMan")] 
public static extern in CalcExampleSum(int a, int b); 

I have a console app which references this managed dll 
the code is as follows 

static Void Main(String args[]) 
{ 
int a= 25; 
int b=34; 
int total=0; 
total= NativeMethods.CalcExampleSum(a,b); 

System.Console.Writeline("The Sum is:{0}",total); 
System.console.Readline(); 
} 

I created my libUnMan.dylib in xcode the code follows 

UnMan.h 

extern "C" 
{ 
    int CalcExampleSum(int a ,int b); 

} 

UnMan.cp 


extern "C" 
{ 
     int CalcExampleSum(int a, int b) 
     {     
    int total=0; 
    total = a + b; 
    return total; 
      } 
} 

 This code works on open SUSE. It builds on all platforms and runs on all except Mac OSX so assume any syntax errors are transcription errors. 
 Where do I have to put the dylib so that it is found? 
 http://www.mono-project.com/Interop_with_Native_Libraries#Library_Handling
I have done the things listed on the page listed above. 
I believe it is a search path problem I have put the libUnMan.dylib everywhere trying to solve the problem still no luck. 
I am open to all ideas!