diff --git a/builtins.go b/builtins.go
index 8d977bc..709e394 100644
--- a/builtins.go
+++ b/builtins.go
@@ -197,10 +197,11 @@ func max(v interface{}, param string) error {
 // regex is the builtin validation function that checks
 // whether the string variable matches a regular expression
 func regex(v interface{}, param string) error {
-	s, ok := v.(string)
-	if !ok {
+	val := reflect.ValueOf(v)
+	if val.Kind() != reflect.String {
 		return ErrUnsupported
 	}
+	s := val.String()
 
 	re, err := regexp.Compile(param)
 	if err != nil {
diff --git a/validator_test.go b/validator_test.go
index 6076024..a6ead74 100644
--- a/validator_test.go
+++ b/validator_test.go
@@ -19,8 +19,8 @@ package validator_test
 import (
 	"testing"
 
+	"github.com/wcl48/go-validator"
 	. "gopkg.in/check.v1"
-	"gopkg.in/validator.v2"
 )
 
 func Test(t *testing.T) {
@@ -266,6 +266,26 @@ func (ms *MySuite) TestBadParameter(c *C) {
 	c.Assert(errs["C"], HasError, validator.ErrBadParameter)
 }
 
+func (ms *MySuite) TestExtendedTypes(c *C) {
+	type MyString string
+	type MyInt int
+	type MyFloat64 float64
+	type test struct {
+		A MyString  `validate:"min=1,max=3,regexp=^[a-z]+$"`
+		B MyInt     `validate:"min=0,max=100"`
+		C MyFloat64 `validate:"min=0,max=100"`
+	}
+
+	t1 := test{
+		A: MyString("abc"),
+		B: MyInt(100),
+		C: MyFloat64(99.999),
+	}
+
+	err := validator.Validate(t1)
+	c.Assert(err, IsNil)
+}
+
 type hasErrorChecker struct {
 	*CheckerInfo
 }