Index: cfssljson/cfssljson.go
--- cfssljson/cfssljson.go.orig	2014-07-12 13:04:59.000000000 +0200
+++ cfssljson/cfssljson.go	2014-07-12 13:35:04.545997296 +0200
@@ -51,15 +51,15 @@
 	}
 
 	if contents, ok := input["cert"]; ok {
-		writeFile(baseName+".pem", contents, 0644)
+		writeFile(baseName+".crt", contents, 0644)
 	} else if contents, ok = input["certificate"]; ok {
-		writeFile(baseName+".pem", contents, 0644)
+		writeFile(baseName+".crt", contents, 0644)
 	}
 
 	if contents, ok := input["key"]; ok {
-		writeFile(baseName+"-key.pem", contents, 0600)
+		writeFile(baseName+".key", contents, 0600)
 	} else if contents, ok = input["private_key"]; ok {
-		writeFile(baseName+"-key.pem", contents, 0600)
+		writeFile(baseName+".key", contents, 0600)
 	}
 
 	if contents, ok := input["csr"]; ok {
@@ -69,6 +69,6 @@
 	}
 
 	if contents, ok := input["bundle"]; ok {
-		writeFile(baseName+"-bundle.pem", contents, 0644)
+		writeFile(baseName+"-bundle.crt", contents, 0644)
 	}
 }