diff --git a/SIN.js b/SIN.js
index d4f15a5..dba5cc3 100644
--- a/SIN.js
+++ b/SIN.js
@@ -11,7 +11,7 @@ function ClassSpec(b) {
     };
     this.data = new Buffer(1 + 1 + payload.length);
     this.__proto__ = this.encodings['binary'];
-    this.prefix(0x18);		// SIN magic number, in numberspace
+    this.prefix(0x0F);		// SIN magic number, in numberspace
     this.type(type);
     this.payload(payload);
   };
diff --git a/SINKey.js b/SINKey.js
index 54bc54a..b80a8a1 100644
--- a/SINKey.js
+++ b/SINKey.js
@@ -19,9 +19,13 @@ function ClassSpec(b) {
 		this.created = timeUtil.curtime();
 	};
 
+	SINKey.prototype.pubkeyHash = function() {
+		return coinUtil.sha256ripe160(this.privKey.public);
+	};
+
 	SINKey.prototype.storeObj = function() {
 		var pubKey = this.privKey.public.toString('hex');
-		var pubKeyHash = coinUtil.sha256ripe160(this.privKey.public);
+		var pubKeyHash = this.pubkeyHash();
 		var sin = new SIN(SIN.SIN_EPHEM, pubKeyHash);
 		var obj = {
 			created: this.created,
diff --git a/Wallet.js b/Wallet.js
index ac5a290..9ca8b79 100644
--- a/Wallet.js
+++ b/Wallet.js
@@ -17,6 +17,7 @@ function ClassSpec(b) {
 		best_hash: null,
 		best_height: -1,
 		keys: [],
+		sin: {},
 		scripts: {},
 	};
 
@@ -76,6 +77,11 @@ function ClassSpec(b) {
 		this.dirty = true;
 	};
 
+	Wallet.prototype.addSIN = function(sinObj) {
+		this.datastore.sin[sinObj.sin] = sinObj;
+		this.dirty = true;
+	};
+
 	Wallet.prototype.findKeyHash = function(pubKeyHash) {
 		var pkhStr = pubKeyHash.toString();