diff --git a/.travis.yml b/.travis.yml
index d36d9f6..46e28a4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,7 +7,7 @@ services:
 
 env:
   global:
-    - VERSION=1.5.0-1
+    - VERSION=1.5.1-1
     - NAME=lua-resty-openidc
     - ROCKSPEC=$NAME-$VERSION.rockspec
     - LUAROCKS=2.3.0
diff --git a/ChangeLog b/ChangeLog
index 7ec6b07..541c518 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,7 @@
   tokens are considered valid. access tokens signed with an
   unsupported algorithm are considered invalid. This is the same
   behavior as has been present in 1.4.1. See #122
+- release 1.5.1
 
 11/15/2017
 - fix return of access_token when renew_access_token_on_expiry = false ; see #121
diff --git a/lib/resty/openidc.lua b/lib/resty/openidc.lua
index 5bbe7fb..cf66471 100644
--- a/lib/resty/openidc.lua
+++ b/lib/resty/openidc.lua
@@ -66,7 +66,7 @@ local supported_token_auth_methods = {
 }
 
 local openidc = {
-  _VERSION = "1.5.0"
+  _VERSION = "1.5.1"
 }
 openidc.__index = openidc
 
@@ -737,6 +737,7 @@ local function openidc_authorization_response(opts, session)
     if is_unsupported_signature_error then
       ngx.log(ngx.WARN, "ignored id_token signature as algorithm '" .. jwt_obj.header.alg .. "' is not supported")
     else
+      ngx.log(ngx.ERR, "id_token '" .. jwt_obj.header.alg .. "' signature verification failed")
       return nil, err, session.data.original_url, session
     end
   end
diff --git a/lua-resty-openidc-1.5.0-1.rockspec b/lua-resty-openidc-1.5.1-1.rockspec
similarity index 97%
rename from lua-resty-openidc-1.5.0-1.rockspec
rename to lua-resty-openidc-1.5.1-1.rockspec
index 31cdcc7..f64b121 100644
--- a/lua-resty-openidc-1.5.0-1.rockspec
+++ b/lua-resty-openidc-1.5.1-1.rockspec
@@ -1,8 +1,8 @@
 package = "lua-resty-openidc"
-version = "1.5.0-1"
+version = "1.5.1-1"
 source = {
     url = "git://github.com/zmartzone/lua-resty-openidc",
-    tag = "v1.5.0",
+    tag = "v1.5.1",
     dir = "lua-resty-openidc"
 }
 description = {