lazy load crypto binding

lib/net.js

@@ -47,15 +47,7 @@ var EINPROGRESS = binding.EINPROGRESS;
 var ENOENT      = binding.ENOENT;
 var EMFILE      = binding.EMFILE;
 var END_OF_FILE = 42;
-
-// Do we have openssl crypto?
-try {
-  var SecureContext = process.binding('crypto').SecureContext;
-  var SecureStream = process.binding('crypto').SecureStream;
-  var haveCrypto = true;
-} catch (e) {
-  var haveCrypto = false;
-}
+var SecureContext, SecureStream; // lazy loaded
 
 // IDLE TIMEOUTS
 //
@@ -544,10 +536,16 @@ function Stream (fd, type) {
 sys.inherits(Stream, events.EventEmitter);
 exports.Stream = Stream;
 
+
 Stream.prototype.setSecure = function (credentials) {
-  if (!haveCrypto) {
+  // Do we have openssl crypto?
+  try {
+    SecureContext = process.binding('crypto').SecureContext;
+    SecureStream = process.binding('crypto').SecureStream;
+  } catch (e) {
     throw new Error('node.js not compiled with openssl crypto support.');
   }
+
   var crypto = require("crypto");
   this.secure = true;
   this.secureEstablished = false;