diff --git a/pkgs/applications/networking/mailreaders/sylpheed/default.nix b/pkgs/applications/networking/mailreaders/sylpheed/default.nix
index 70d01f5df3ea..0f8b4f00c8ba 100644
--- a/pkgs/applications/networking/mailreaders/sylpheed/default.nix
+++ b/pkgs/applications/networking/mailreaders/sylpheed/default.nix
@@ -25,7 +25,8 @@ stdenv.mkDerivation {
     ++ optional sslSupport openssl
     ++ optional gpgSupport gpgme;
 
-  configureFlags = optionalString sslSupport "--enable-ssl";
+  configureFlags = optional sslSupport "--enable-ssl"
+                ++ optional gpgSupport "--enable-gpgme";
 
   meta = {
     homepage = http://sylpheed.sraoss.jp/en/;