gistfile1.txt

--- node_modules/mongoose/lib/mongoose/schema/number.js	2011-06-08 14:42:22.000000000 +0200
+++ version2	2011-06-08 14:40:37.000000000 +0200
@@ -84,8 +84,11 @@
 SchemaNumber.prototype.cast = function (value, doc) {
   if (!isNaN(value)){
     if (null === value) return value;
-    if ('' === value) return null;
-    if ('string' === typeof value) value = Number(value);
+    if ('string' === typeof value) {
+        value = value.trim();
+        if ('' === value) return null;
+        value = Number(value);
+    }
     if (value instanceof Number || typeof value == 'number' ||
        (value.toString && value.toString() == Number(value)))
       return new MongooseNumber(value, this.path, doc);