I think it dislikes parallel building due to subdir handling

sio/sio.spec

@@ -33,7 +33,7 @@ Distribution: OpenPKG [PLUS]
 Group:        System
 License:      MIT/X11-style
 Version:      0.9.1
-Release:      20030617
+Release:      20030630
 
 #   package options
 %option       with_ex    no
@@ -98,7 +98,7 @@ AutoReqProv:  no
         --enable-zlib \
 %endif
         --disable-shared
-    %{l_make} %{l_mflags -O}
+    %{l_make} %{l_mflags}
 
 %install
     rm -rf $RPM_BUILD_ROOT