diff --git a/CHANGELOG.md b/CHANGELOG.md
index 352b90c..9ca773c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 4.2.1
+
+  - Fix sub-second timestamp math
+
 ## 4.2.0
 
   - Added Cisco ACI to list of known working Netflow v9 exporters
diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index ea38a8f..d4e6933 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -10,6 +10,7 @@ Contributors:
 * Bjørn Ruberg (bruberg)
 * Colin Surprenant (colinsurprenant)
 * Daniel Nägele (analogbyte)
+* Dan Hermann (danhermann)
 * Diyaldine Maoulida
 * Evgeniy Sudyr (ejectck)
 * G.J. Moed (gjmoed)
diff --git a/logstash-codec-netflow.gemspec b/logstash-codec-netflow.gemspec
index 2bc5927..c119ea7 100644
--- a/logstash-codec-netflow.gemspec
+++ b/logstash-codec-netflow.gemspec
@@ -1,7 +1,7 @@
 Gem::Specification.new do |s|
 
   s.name            = 'logstash-codec-netflow'
-  s.version         = '4.2.0'
+  s.version         = '4.2.1'
   s.licenses        = ['Apache License (2.0)']
   s.summary         = "Reads Netflow v5, Netflow v9 and IPFIX data"
   s.description     = "This gem is a Logstash plugin required to be installed on top of the Logstash core pipeline using $LS_HOME/bin/logstash-plugin install gemname. This gem is not a stand-alone program"