diff --git a/tests/mpn/Makefile.am b/tests/mpn/Makefile.am
index e594241b..95b24ebd 100644
--- a/tests/mpn/Makefile.am
+++ b/tests/mpn/Makefile.am
@@ -30,7 +30,8 @@ check_PROGRAMS = t-asmtype t-aors_1 t-divrem_1 t-fat t-get_d \
   t-neg t-mulmod_2expp1 t-mulmod_2expm1 t-tdiv_q t-sb_divappr_q \
   t-dc_divappr_q_n t-inv_divappr_q_n t-invert t-sb_div_q t-sb_div_qr \
   t-dc_div_q t-dc_div_qr t-dc_divappr_q t-dc_div_qr_n t-inv_divappr_q \
-  t-inv_div_q t-inv_div_qr t-inv_div_qr_n t-tdiv_qr t-sb_bdiv_q
+  t-inv_div_q t-inv_div_qr t-inv_div_qr_n t-tdiv_qr t-sb_bdiv_q \
+  t-sb_bdiv_qr
   
 if ENABLE_STATIC
 if ENABLE_SHARED
diff --git a/tests/mpn/Makefile.in b/tests/mpn/Makefile.in
index 06290fd3..dff31b10 100644
--- a/tests/mpn/Makefile.in
+++ b/tests/mpn/Makefile.in
@@ -67,7 +67,7 @@ check_PROGRAMS = t-asmtype$(EXEEXT) t-aors_1$(EXEEXT) \
 	t-dc_div_qr_n$(EXEEXT) t-inv_divappr_q$(EXEEXT) \
 	t-inv_div_q$(EXEEXT) t-inv_div_qr$(EXEEXT) \
 	t-inv_div_qr_n$(EXEEXT) t-tdiv_qr$(EXEEXT) \
-	t-sb_bdiv_q$(EXEEXT) $(am__EXEEXT_1)
+	t-sb_bdiv_q$(EXEEXT) t-sb_bdiv_qr$(EXEEXT) $(am__EXEEXT_1)
 @ENABLE_SHARED_TRUE@@ENABLE_STATIC_TRUE@am__append_1 = st_fat st_instrument
 subdir = tests/mpn
 DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
@@ -266,6 +266,11 @@ t_sb_bdiv_q_OBJECTS = t-sb_bdiv_q.$(OBJEXT)
 t_sb_bdiv_q_LDADD = $(LDADD)
 t_sb_bdiv_q_DEPENDENCIES = $(top_builddir)/tests/libtests.la \
 	$(top_builddir)/libmpir.la
+t_sb_bdiv_qr_SOURCES = t-sb_bdiv_qr.c
+t_sb_bdiv_qr_OBJECTS = t-sb_bdiv_qr.$(OBJEXT)
+t_sb_bdiv_qr_LDADD = $(LDADD)
+t_sb_bdiv_qr_DEPENDENCIES = $(top_builddir)/tests/libtests.la \
+	$(top_builddir)/libmpir.la
 t_sb_div_q_SOURCES = t-sb_div_q.c
 t_sb_div_q_OBJECTS = t-sb_div_q.$(OBJEXT)
 t_sb_div_q_LDADD = $(LDADD)
@@ -321,9 +326,9 @@ SOURCES = $(st_fat_SOURCES) $(st_instrument_SOURCES) t-addadd_n.c \
 	t-inv_divappr_q.c t-inv_divappr_q_n.c t-invert.c t-iord_u.c \
 	t-lorrshift1.c t-mp_bases.c t-mullow_basecase.c t-mullowhigh.c \
 	t-mulmid.c t-mulmod_2expm1.c t-mulmod_2expp1.c t-neg.c \
-	t-perfsqr.c t-redc_basecase.c t-sb_bdiv_q.c t-sb_div_q.c \
-	t-sb_div_qr.c t-sb_divappr_q.c t-scan.c t-subadd_n.c \
-	t-tdiv_q.c t-tdiv_qr.c
+	t-perfsqr.c t-redc_basecase.c t-sb_bdiv_q.c t-sb_bdiv_qr.c \
+	t-sb_div_q.c t-sb_div_qr.c t-sb_divappr_q.c t-scan.c \
+	t-subadd_n.c t-tdiv_q.c t-tdiv_qr.c
 DIST_SOURCES = $(am__st_fat_SOURCES_DIST) \
 	$(am__st_instrument_SOURCES_DIST) t-addadd_n.c t-addsub_n.c \
 	t-aors_1.c t-asmtype.c t-dc_div_q.c t-dc_div_qr.c \
@@ -333,9 +338,9 @@ DIST_SOURCES = $(am__st_fat_SOURCES_DIST) \
 	t-inv_divappr_q.c t-inv_divappr_q_n.c t-invert.c t-iord_u.c \
 	t-lorrshift1.c t-mp_bases.c t-mullow_basecase.c t-mullowhigh.c \
 	t-mulmid.c t-mulmod_2expm1.c t-mulmod_2expp1.c t-neg.c \
-	t-perfsqr.c t-redc_basecase.c t-sb_bdiv_q.c t-sb_div_q.c \
-	t-sb_div_qr.c t-sb_divappr_q.c t-scan.c t-subadd_n.c \
-	t-tdiv_q.c t-tdiv_qr.c
+	t-perfsqr.c t-redc_basecase.c t-sb_bdiv_q.c t-sb_bdiv_qr.c \
+	t-sb_div_q.c t-sb_div_qr.c t-sb_divappr_q.c t-scan.c \
+	t-subadd_n.c t-tdiv_q.c t-tdiv_qr.c
 ETAGS = etags
 CTAGS = ctags
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
@@ -643,6 +648,9 @@ t-redc_basecase$(EXEEXT): $(t_redc_basecase_OBJECTS) $(t_redc_basecase_DEPENDENC
 t-sb_bdiv_q$(EXEEXT): $(t_sb_bdiv_q_OBJECTS) $(t_sb_bdiv_q_DEPENDENCIES) 
 	@rm -f t-sb_bdiv_q$(EXEEXT)
 	$(LINK) $(t_sb_bdiv_q_OBJECTS) $(t_sb_bdiv_q_LDADD) $(LIBS)
+t-sb_bdiv_qr$(EXEEXT): $(t_sb_bdiv_qr_OBJECTS) $(t_sb_bdiv_qr_DEPENDENCIES) 
+	@rm -f t-sb_bdiv_qr$(EXEEXT)
+	$(LINK) $(t_sb_bdiv_qr_OBJECTS) $(t_sb_bdiv_qr_LDADD) $(LIBS)
 t-sb_div_q$(EXEEXT): $(t_sb_div_q_OBJECTS) $(t_sb_div_q_DEPENDENCIES) 
 	@rm -f t-sb_div_q$(EXEEXT)
 	$(LINK) $(t_sb_div_q_OBJECTS) $(t_sb_div_q_LDADD) $(LIBS)
diff --git a/tests/mpn/t-sb_bdiv_qr.c b/tests/mpn/t-sb_bdiv_qr.c
new file mode 100644
index 00000000..379c36f1
--- /dev/null
+++ b/tests/mpn/t-sb_bdiv_qr.c
@@ -0,0 +1,107 @@
+/* Test mpn_sb_bdiv_qr.
+
+Copyright 2002 Free Software Foundation, Inc.
+Copyright 2009, 2010 William Hart
+
+This file is part of the MPIR Library.
+
+The MPIR Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or (at your
+option) any later version.
+
+The MPIR Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the MPIR Library; see the file COPYING.LIB.  If not, write to
+the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+MA 02110-1301, USA. */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "mpir.h"
+#include "gmp-impl.h"
+#include "longlong.h"
+#include "tests.h"
+
+#if defined(_MSC_VER) || defined(__MINGW32__)
+#define random rand
+#endif
+
+#define MAX_LIMBS 40
+#define ITERS 10000
+   
+/* Check schoolboy hensel division routine. */
+void
+check_sb_bdiv_qr (void)
+{
+   mp_limb_t np[2*MAX_LIMBS];
+   mp_limb_t np2[2*MAX_LIMBS];
+   mp_limb_t rp[2*MAX_LIMBS];
+   mp_limb_t dp[2*MAX_LIMBS];
+   mp_limb_t qp[2*MAX_LIMBS];
+   mp_limb_t dip, cy;
+
+   mp_size_t nn, rn, dn, qn;
+
+   gmp_randstate_t rands;
+
+   int i, j, s;
+   gmp_randinit_default(rands);
+  
+   for (i = 0; i < ITERS; i++)
+   {
+      dn = (random() % (MAX_LIMBS - 2)) + 3;
+      nn = (random() % (MAX_LIMBS - 1)) + dn + 1;
+      qn = nn - dn;
+
+      mpn_rrandom (np, rands, nn);
+      mpn_rrandom (dp, rands, dn);
+      
+      dp[0] |= 1;
+     
+      MPN_COPY(np2, np, nn);
+      
+      modlimb_invert(dip, dp[0]);
+      dip = -dip;
+      
+      mpn_sb_bdiv_qr(qp, np, nn, dp, dn, dip);
+      
+      if (qn)
+      {
+         if (qn >= dn) mpn_mul(rp, qp, qn, dp, dn);
+         else mpn_mul(rp, dp, dn, qp, qn);
+      } else
+         MPN_ZERO(rp, nn);
+      
+      mpn_sub_n(rp, np2, rp, nn);
+      
+      if (mpn_cmp(rp + qn, np + qn, dn) != 0)
+      { 
+         printf("failed: quotient wrong!\n");
+         printf ("nn = %lu, dn = %lu, qn = %lu\n\n", nn, dn, qn);
+         gmp_printf (" np: %Nx\n\n", np2, nn);
+         gmp_printf (" dp: %Nx\n\n", dp, dn);
+         gmp_printf (" qp: %Nx\n\n", qp, qn);
+         gmp_printf (" rp: %Nx\n\n", rp, qn);
+         abort ();
+      }
+   }
+
+   gmp_randclear(rands);
+}
+
+int
+main (void)
+{
+  tests_start ();
+
+  check_sb_bdiv_qr ();
+  
+  tests_end ();
+  exit (0);
+}