diff --git a/rpm/macros.kernel-source b/rpm/macros.kernel-source
index fb4f637..6bc027d 100644
--- a/rpm/macros.kernel-source
+++ b/rpm/macros.kernel-source
@@ -1,9 +1,11 @@
 # A few cross-distro definitions:
-%if 0%{?suse_version} > 1500 || 0%{?sle_version} > 150300
-%define kernel_build_shell_package bash-sh
-%else
-%define kernel_build_shell_package %nil
-%endif
+%kernel_build_shell_package %{lua: \
+if ((tonumber(rpm.expand("0%{?suse_version}")) > 1500) or (tonumber(rpm.expand("0%{?sle_version}")) > 150300)) then \
+    print( "bash-sh" ) \
+else \
+    print(  "" ) \
+end \
+}
 %kernel_module_package_release 1
 %kernel_module_package_buildreqs modutils kernel-syms kmod-compat %kernel_build_shell_package