diff --git a/rpm/lemonldap-ng.spec b/rpm/lemonldap-ng.spec
index a139281a8..d105f9057 100644
--- a/rpm/lemonldap-ng.spec
+++ b/rpm/lemonldap-ng.spec
@@ -77,6 +77,7 @@ BuildRequires:  perl(Crypt::Rijndael)
 BuildRequires:  perl(Crypt::URandom)
 BuildRequires:  perl(Cwd)
 BuildRequires:  perl(Data::Dumper)
+BuildRequires:  perl(DateTime::Format::RFC3339)
 BuildRequires:  perl(DBI)
 BuildRequires:  perl(Digest::HMAC_SHA1)
 BuildRequires:  perl(Digest::MD5)