diff --git a/make-gnucash-patch.in b/make-gnucash-patch.in
index add915a1ee..b4a6979ec8 100644
--- a/make-gnucash-patch.in
+++ b/make-gnucash-patch.in
@@ -113,6 +113,7 @@ configure
 gnucash.engine.i
 gnucash.pm
 gnucash-engine-perl5_wrap.c
+gnucash-engine-perl5_wrap_int.c
 g-wrap-guile
 libgncengine.la
 libgwrapguile.la
diff --git a/src/optional/swig/.cvsignore b/src/optional/swig/.cvsignore
index b69db4eb90..ab9675e230 100644
--- a/src/optional/swig/.cvsignore
+++ b/src/optional/swig/.cvsignore
@@ -5,5 +5,6 @@ Makefile
 *.la
 gnucash.engine.i
 gnucash-engine-perl5_wrap.c
+gnucash-engine-perl5_wrap_int.c
 gnucash.engine_wrap.doc
 gnucash.pm
diff --git a/src/optional/swig/Makefile.am b/src/optional/swig/Makefile.am
index abee171277..1ee43cd7d9 100644
--- a/src/optional/swig/Makefile.am
+++ b/src/optional/swig/Makefile.am
@@ -18,7 +18,8 @@ noinst_HEADERS = \
 EXTRA_DIST = \
   .cvsignore \
   examples/scan-acct.pl \
-  perl5_swig_annotations.i
+  perl5_swig_annotations.i \
+  gnucash-swig-defines.c
 
 CFLAGS = @CFLAGS@ ${GNOME_CFLAGS} -Dbool=char
 
@@ -97,8 +98,13 @@ gnucash.engine.i: ${SWIG_INPUT_HDRS}  perl5_swig_annotations.i
 
 CLEANFILES += gnucash.engine.i gnucash.engine_wrap.doc
 
-gnucash-engine-perl5_wrap.c: gnucash.engine.i
+gnucash-engine-perl5_wrap_int.c: gnucash.engine.i
 	${SWIG} -perl5 -I.. -I${top_srcdir}/src/engine -o $@ $< 
+CLEANFILES += gnucash-engine-perl5_wrap_int.c
+
+gnucash-engine-perl5_wrap.c: gnucash-swig-defines.c \
+                             gnucash-engine-perl5_wrap_int.c
+	cat gnucash-swig-defines.c gnucash-engine-perl5_wrap_int.c > $@
 CLEANFILES += gnucash-engine-perl5_wrap.c
 
 CLEANFILES += gnucash.pm gnucash.so
diff --git a/src/optional/swig/Makefile.in b/src/optional/swig/Makefile.in
index 2db59241d9..f1c25fe720 100644
--- a/src/optional/swig/Makefile.in
+++ b/src/optional/swig/Makefile.in
@@ -130,7 +130,7 @@ libgncswig_la_LDFLAGS = -version-info 1:1:1
 noinst_HEADERS =    helperfuncs.h
 
 
-EXTRA_DIST =    .cvsignore   examples/scan-acct.pl   perl5_swig_annotations.i
+EXTRA_DIST =    .cvsignore   examples/scan-acct.pl   perl5_swig_annotations.i   gnucash-swig-defines.c
 
 
 CFLAGS = @CFLAGS@ ${GNOME_CFLAGS} -Dbool=char
@@ -144,7 +144,7 @@ libgncswig_la_LIBADD =    @GLIB_LIBS@   ${top_srcdir}/src/engine/AccInfo.lo   ${
 SWIG_INPUT_HDRS :=    ${top_srcdir}/src/engine/AccInfo.h   ${top_srcdir}/src/engine/Account.h   ${top_srcdir}/src/engine/DateUtils.h   ${top_srcdir}/src/engine/FileIO.h   ${top_srcdir}/src/engine/GNCId.h   ${top_srcdir}/src/engine/Group.h   ${top_srcdir}/src/engine/LedgerUtils.h   ${top_srcdir}/src/engine/Query.h   ${top_srcdir}/src/engine/Queue.h   ${top_srcdir}/src/engine/Scrub.h   ${top_srcdir}/src/engine/Session.h   ${top_srcdir}/src/engine/TransLog.h   ${top_srcdir}/src/engine/Transaction.h   ${top_srcdir}/src/engine/date.h
 
 
-CLEANFILES =  gnucash.engine.i gnucash.engine_wrap.doc gnucash-engine-perl5_wrap.c gnucash.pm gnucash.so
+CLEANFILES =  gnucash.engine.i gnucash.engine_wrap.doc gnucash-engine-perl5_wrap_int.c gnucash-engine-perl5_wrap.c gnucash.pm gnucash.so
 mkinstalldirs = $(SHELL) $(top_srcdir)/mkinstalldirs
 CONFIG_HEADER = ../../../config.h
 CONFIG_CLEAN_FILES = 
@@ -476,9 +476,13 @@ gnucash.engine.i: ${SWIG_INPUT_HDRS}  perl5_swig_annotations.i
           echo "%include `basename $$file`" >> $@; \
 	done
 
-gnucash-engine-perl5_wrap.c: gnucash.engine.i
+gnucash-engine-perl5_wrap_int.c: gnucash.engine.i
 	${SWIG} -perl5 -I.. -I${top_srcdir}/src/engine -o $@ $< 
 
+gnucash-engine-perl5_wrap.c: gnucash-swig-defines.c \
+                             gnucash-engine-perl5_wrap_int.c
+	cat gnucash-swig-defines.c gnucash-engine-perl5_wrap_int.c > $@
+
 # We have to do this because otherwise automake insists on putting
 # these files into the dist tarfile.  If there's a a better way,
 # by all means, let us know...
diff --git a/src/optional/swig/gnucash-swig-defines.c b/src/optional/swig/gnucash-swig-defines.c
new file mode 100644
index 0000000000..3ac531362a
--- /dev/null
+++ b/src/optional/swig/gnucash-swig-defines.c
@@ -0,0 +1,3 @@
+#define sv_undef PL_sv_undef
+#define sv_yes PL_sv_yes
+#define na PL_na