diff --git a/kimono.spec b/kimono.spec
index ba21988..11ed26e 100644
--- a/kimono.spec
+++ b/kimono.spec
@@ -32,7 +32,7 @@ BuildRequires: smokekde-devel >= %{version}
 %{?_kde4_version:Requires: qyoto%{?_isa} >= %{_kde4_version}}
 %{?_kde4_version:Requires: smokekde%{?_isa} >= %{_kde4_version}}
 
-ExclusiveArch: %{mono_arches}
+%{?mono_arches:ExclusiveArch: %{mono_arches}}
 
 %description
 %{summary}.