diff --git a/integrationTests/helloGretty/build.gradle b/integrationTests/helloGretty/build.gradle
index c60575368..33e1a2f66 100644
--- a/integrationTests/helloGretty/build.gradle
+++ b/integrationTests/helloGretty/build.gradle
@@ -13,6 +13,7 @@ gretty {
   // Possible servletContainer values are 'jetty7', 'jetty8', 'jetty9', 'tomcat85', 'tomcat9'. Default is 'jetty9'.
   // servletContainer = 'tomcat8'
   // httpsEnabled = true
+  httpIdleTimeout = 424242
 }
 
 war {
diff --git a/integrationTests/helloGrettySecure/build.gradle b/integrationTests/helloGrettySecure/build.gradle
index 150395bbf..04d4d5032 100644
--- a/integrationTests/helloGrettySecure/build.gradle
+++ b/integrationTests/helloGrettySecure/build.gradle
@@ -12,6 +12,7 @@ dependencies {
 gretty {
   httpEnabled = false
   httpsEnabled = true
+  httpsIdleTimeout = 424242
   // Possible servletContainer values are 'jetty7', 'jetty8', 'jetty9', 'tomcat85', 'tomcat9'. Default is 'jetty9'.
   servletContainer = 'jetty9'
   realm 'auth'
diff --git a/libs/gretty-runner-tomcat/src/main/groovy/org/akhikhl/gretty/TomcatServerConfigurer.groovy b/libs/gretty-runner-tomcat/src/main/groovy/org/akhikhl/gretty/TomcatServerConfigurer.groovy
index 86904d74b..cd897cba3 100644
--- a/libs/gretty-runner-tomcat/src/main/groovy/org/akhikhl/gretty/TomcatServerConfigurer.groovy
+++ b/libs/gretty-runner-tomcat/src/main/groovy/org/akhikhl/gretty/TomcatServerConfigurer.groovy
@@ -189,7 +189,7 @@ class TomcatServerConfigurer {
         sslConfig.truststorePassword = params.sslTrustStorePassword
 
       if(params.httpsIdleTimeout)
-        httpsConn.setProperty('keepAliveTimeout', params.httpsIdleTimeout)
+        httpsConn.setProperty('keepAliveTimeout', params.httpsIdleTimeout.toString())
 
       httpsConn.setProperty('maxPostSize', '0')  // unlimited