diff --git a/admin/pki/team.go b/admin/pki/team.go
index 2263e32c..6aa5c75c 100644
--- a/admin/pki/team.go
+++ b/admin/pki/team.go
@@ -3,6 +3,7 @@ package pki
 import (
 	"fmt"
 	"io/ioutil"
+	"math"
 	"os"
 	"path"
 	"strconv"
@@ -12,7 +13,7 @@ import (
 const SymlinkPrefix = "_AUTH_ID_"
 
 func GetCertificateAssociation(serial uint64) string {
-	return fmt.Sprintf(SymlinkPrefix + "%0X", serial)
+	return fmt.Sprintf(SymlinkPrefix + "%0[2]*[1]X", serial, int(math.Ceil(math.Log2(float64(serial))/8)*2))
 }
 
 func GetAssociations(dirname string) (assocs []string, err error) {