diff --git a/openttd.spec b/openttd.spec
index f4cd82d..935464d 100644
--- a/openttd.spec
+++ b/openttd.spec
@@ -49,6 +49,7 @@ the AI.
 %prep
 %autosetup -p1 -n %{name}-%{version}%{?prever:-%{prever}}
 
+sed -i "s|/usr|%{_prefix}|g" config.lib
 
 %build
 export CFLAGS="$RPM_OPT_FLAGS"