diff --git a/js/src/jsstr.h b/js/src/jsstr.h
index 254b98dda926..8981341cd95c 100644
--- a/js/src/jsstr.h
+++ b/js/src/jsstr.h
@@ -752,15 +752,18 @@ extern const bool js_alnum[];
 
 #define JS_ISDIGIT(c)   (JS_CTYPE(c) == JSCT_DECIMAL_DIGIT_NUMBER)
 
+const jschar BYTE_ORDER_MARK = 0xFEFF;
+const jschar NO_BREAK_SPACE  = 0x00A0;
+
 static inline bool
 JS_ISSPACE(jschar c)
 {
     unsigned w = c;
 
     if (w < 256)
-        return (w <= ' ' && (w == ' ' || (9 <= w && w <= 0xD))) || w == 0xA0;
+        return (w <= ' ' && (w == ' ' || (9 <= w && w <= 0xD))) || w == NO_BREAK_SPACE;
 
-    return (JS_CCODE(w) & 0x00070000) == 0x00040000;
+    return w == BYTE_ORDER_MARK || (JS_CCODE(w) & 0x00070000) == 0x00040000;
 }
 
 #define JS_ISPRINT(c)   ((c) < 128 && isprint(c))
diff --git a/js/src/tests/ecma/GlobalObject/15.1.2.2-1.js b/js/src/tests/ecma/GlobalObject/15.1.2.2-1.js
index e7cfdf14a7c4..daf013ca2511 100644
--- a/js/src/tests/ecma/GlobalObject/15.1.2.2-1.js
+++ b/js/src/tests/ecma/GlobalObject/15.1.2.2-1.js
@@ -218,6 +218,8 @@ for ( var space = " ", HEX_STRING = "0x0", HEX_VALUE = 0, POWER = 0;
   HEX_VALUE += Math.pow(16,POWER)*15;
 }
 
+new TestCase(SECTION, "parseInt(BOM + '123', 10)", 123, parseInt("\uFEFF" + "123", 10));
+
 // a few tests with negative numbers
 for ( HEX_STRING = "-0x0", HEX_VALUE = 0, POWER = 0; POWER < 15; POWER++, HEX_STRING = HEX_STRING +"f" ) {
   new TestCase( SECTION, "parseInt("+HEX_STRING+")",    HEX_VALUE,  parseInt(HEX_STRING) );