ReadLn doesnt't work

    program testRead;

    type Signature = array[1..5] of integer;

    var m:Signature;

    begin
      ReadLn(m[1]);
      ReadLn(m[2]);
      ReadLn(m[3]);
      Write('->',m[1],' ',m[2],' ',m[3]);
    end.

btpc.exe <testRead.pas >test.exe && test.exe
12
34
56
->12 0 0

ReadLn doesn't work if called a couple of times. 
If change ReadLn -> Read, then it works as intented