[50分]postmessage可以传送负数吗?

const
kill=wm_user+1000;发送的代码
procedure TForm1.Button1Click(Sender: TObject);
var
myhwnd:hwnd;
sendcallmsg:PMYMSG;
begin
myhwnd:=findwindow(nil,'记事本1.txt');
postmessage(zxhwnd,sendcallmsg.WM_paolu,100,-10);
end;
接收的代码
function sethookproc(nCode: integer; WParam: longint; msg: longint): longint;stdcall; 
begin
 if pmsg(msg)^.message= kill then
  begin
     ppaolu(pmsg(msg)^.wParam,pmsg(msg)^.lParam);
     showmessage('lParam:'+inttostr(pmsg(msg)^.lParam));
     result:=callnexthookex(myhook,ncode,wparam,msg);
     exit;
  end;
end;
接收后会显示lparam里是一个很大的正数
接收wparam里的正数就没问题.我该如何解决？是不是不能传送负数？;