diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 827b1f0..cf0d29f 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -51,6 +51,7 @@
    -  Path constants BASEPATH, APPPATH and VIEWPATH are now (internally) defined as absolute paths.
    -  Updated email validation methods to use ``filter_var()`` instead of PCRE.
    -  Changed environment defaults to report all errors in 'development' and only fatal ones in 'testing' and 'production' but only display them in 'development'.
+   -  Updated ip_address lengths from 16 to 45 for supporting ipv6 address on trackback library and captcha helper.
 
 -  Helpers
 
diff --git a/user_guide_src/source/helpers/captcha_helper.rst b/user_guide_src/source/helpers/captcha_helper.rst
index 48095a1..9024473 100644
--- a/user_guide_src/source/helpers/captcha_helper.rst
+++ b/user_guide_src/source/helpers/captcha_helper.rst
@@ -102,7 +102,7 @@
 	CREATE TABLE captcha (  
 		captcha_id bigint(13) unsigned NOT NULL auto_increment,  
 		captcha_time int(10) unsigned NOT NULL,  
-		ip_address varchar(16) default '0' NOT NULL,  
+		ip_address varchar(45) NOT NULL,  
 		word varchar(20) NOT NULL,  
 		PRIMARY KEY `captcha_id` (`captcha_id`),  
 		KEY `word` (`word`)
diff --git a/user_guide_src/source/libraries/trackback.rst b/user_guide_src/source/libraries/trackback.rst
index 07b2b21..f9e0df8 100644
--- a/user_guide_src/source/libraries/trackback.rst
+++ b/user_guide_src/source/libraries/trackback.rst
@@ -114,7 +114,7 @@
 	 excerpt text NOT NULL,
 	 blog_name varchar(100) NOT NULL,
 	 tb_date int(10) NOT NULL,
-	 ip_address varchar(16) NOT NULL,
+	 ip_address varchar(45) NOT NULL,
 	 PRIMARY KEY `tb_id` (`tb_id`),
 	 KEY `entry_id` (`entry_id`)
 	);