diff --git a/build.gradle b/build.gradle
index ac1bb2be..09f9968d 100644
--- a/build.gradle
+++ b/build.gradle
@@ -38,6 +38,10 @@ subprojects {
             stripJar(it.archivePath)
         }
     }
+    
+    tasks.withType(Jar) {
+        metadataCharset = "US-ASCII"
+    }
 }
 import java.util.jar.*
 void stripJar(File file) {
diff --git a/gui/build.gradle b/gui/build.gradle
index 8fe4b6ce..ef663579 100644
--- a/gui/build.gradle
+++ b/gui/build.gradle
@@ -158,25 +158,25 @@ task griffonManifest {
         manifest.mkdirs()
         
         def controllerFile = new File(manifest, "griffon.core.artifact.GriffonController")
-        controllerFile.withPrintWriter {writer ->
+        controllerFile.withPrintWriter("US-ASCII", {writer ->
             controllers.each {controller ->
                 writer.println(controller)
             }
-        }
+        })
 
         def modelsFile = new File(manifest, "griffon.core.artifact.GriffonModel")
-        modelsFile.withPrintWriter {writer ->
+        modelsFile.withPrintWriter("US-ASCII", {writer ->
             models.each {model ->
                 writer.println(model)
             }
-        }
+        })
 
         def viewsFile = new File(manifest, "griffon.core.artifact.GriffonView")
-        viewsFile.withPrintWriter {writer ->
+        viewsFile.withPrintWriter("US-ASCII", {writer ->
             views.each {view ->
                 writer.println(view)
             }
-        }
+        })
     }
 }