diff --git a/mozilla/js/ref/jsregexp.c b/mozilla/js/ref/jsregexp.c
index 9c7ec8fe3df..ad8db0e0148 100644
--- a/mozilla/js/ref/jsregexp.c
+++ b/mozilla/js/ref/jsregexp.c
@@ -1476,8 +1476,7 @@ OptimizeRegExp(CompilerState *state, RENode *ren)
 		    len = 1;
 		}
 		cx = state->context;
-		PR_ARENA_ALLOCATE(cp, &cx->tempPool,
-                                            (len + 1) * sizeof(jschar));
+		PR_ARENA_ALLOCATE(cp, &cx->tempPool, (len+2) * sizeof(jschar));
 		if (!cp) {
 		    JS_ReportOutOfMemory(cx);
 		    return JS_FALSE;
@@ -1973,7 +1972,6 @@ js_NewRegExp(JSContext *cx, JSString *str, uintN flags)
     if (!end || !SetNext(&state, ren, end))
 	goto out;
 
-
     if (!AnchorRegExp(&state, ren))
 	goto out;
     if (!OptimizeRegExp(&state, ren))