Need to quote test for posix_threads on HPUX11
diff --git a/configure.in b/configure.in
index 519bbd7..e24f73c 100644
--- a/configure.in
+++ b/configure.in
@@ -1360,7 +1360,7 @@
     THREADOBJ="Python/thread.o"
     USE_THREAD_MODULE=""])
 
-    if test $posix_threads != "yes"; then     
+    if test "$posix_threads" != "yes"; then     
       AC_CHECK_LIB(thread, thr_create, [AC_DEFINE(WITH_THREAD)
       LIBS="$LIBS -lthread"
       THREADOBJ="Python/thread.o"