diff --git a/configure.ac b/configure.ac
index f2814dd1d..e94bd30c4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -963,6 +963,17 @@ else
 *** we need the support of the New Portable Threads Library.
 ***]])
 fi
+#
+# Enable debugging of nPth
+#
+AC_ARG_ENABLE(npth-debug,
+   AC_HELP_STRING([--enable-npth-debug],
+                  [build with debug version of npth]),
+                  [if test $enableval = yes ; then
+                     AC_DEFINE(NPTH_ENABLE_DEBUG,1,
+                              [Build with debug version of nPth])
+                  fi])
+
 
 
 #