diff --git a/src/core.js b/src/core.js
index f2e4d65..4630a9f 100644
--- a/src/core.js
+++ b/src/core.js
@@ -1057,12 +1057,12 @@ $.extend( $.validator, {
 
 		if ( $.validator.autoCreateRanges ) {
 			// auto-create ranges
-			if ( rules.min && rules.max ) {
+			if ( rules.min != null && rules.max != null ) {
 				rules.range = [ rules.min, rules.max ];
 				delete rules.min;
 				delete rules.max;
 			}
-			if ( rules.minlength && rules.maxlength ) {
+			if ( rules.minlength != null && rules.maxlength != null ) {
 				rules.rangelength = [ rules.minlength, rules.maxlength ];
 				delete rules.minlength;
 				delete rules.maxlength;
diff --git a/test/rules.js b/test/rules.js
index 5d405c4..ae7d8e7 100644
--- a/test/rules.js
+++ b/test/rules.js
@@ -84,19 +84,19 @@ test("rules(), merge min/max to range, minlength/maxlength to rangelength", func
 	$("#testForm1clean").validate({
 		rules: {
 			firstnamec: {
-				min: 5,
-				max: 12
+				min: -15,
+				max: 0
 			},
 			lastname: {
-				minlength: 2,
-				maxlength: 8
+				minlength: 0,
+				maxlength: 10
 			}
 		}
 	});
 
-	deepEqual( $("#firstnamec").rules(), { range: [ 5, 12 ] } );
+	deepEqual( $("#firstnamec").rules(), { range: [ -15, 0 ] } );
+	deepEqual( $("#lastnamec").rules(), { rangelength: [ 0, 10 ] } );
 
-	deepEqual( $("#lastnamec").rules(), { rangelength: [ 2, 8 ] } );
 	jQuery.validator.autoCreateRanges = false;
 });