diff -uNr build.orig/configure.ac build/configure.ac
--- build.orig/configure.ac	2010-05-24 02:19:58.000000000 +0200
+++ build/configure.ac	2010-05-24 19:35:42.000000000 +0200
@@ -194,6 +194,22 @@
 AC_SUBST(ICONV_INCLUDE_DIRS)
 AC_SUBST(ICONV_LIB_DIRS)
 
+dnl Allow to specify gmp options to the toplevel configure script
+dnl so they can be properly passed to sub-builds.
+
+AC_ARG_WITH([gmp-includes],
+  [AC_HELP_STRING([--with-gmp-includes],
+    [directory containing gmp.h])],
+    [GMP_INCLUDE_DIRS=$withval])
+
+AC_ARG_WITH([gmp-libraries],
+  [AC_HELP_STRING([--with-gmp-libraries],
+    [directory containing gmp library])],
+    [GMP_LIB_DIRS=$withval])
+
+AC_SUBST(GMP_INCLUDE_DIRS)
+AC_SUBST(GMP_LIB_DIRS)
+
 dnl--------------------------------------------------------------------
 dnl * Choose host(/target/build) platform
 dnl--------------------------------------------------------------------
diff -uNr build.orig/mk/config.mk.in build/mk/config.mk.in
--- build.orig/mk/config.mk.in	2010-05-24 02:20:02.000000000 +0200
+++ build/mk/config.mk.in	2010-05-24 19:36:43.000000000 +0200
@@ -785,3 +785,5 @@
 ICONV_INCLUDE_DIRS = @ICONV_INCLUDE_DIRS@
 ICONV_LIB_DIRS = @ICONV_LIB_DIRS@
 
+GMP_INCLUDE_DIRS = @GMP_INCLUDE_DIRS@
+GMP_LIB_DIRS = @GMP_LIB_DIRS@
diff -uNr build.orig/rules/build-package-data.mk build/rules/build-package-data.mk
--- build.orig/rules/build-package-data.mk	2010-05-24 02:20:10.000000000 +0200
+++ build/rules/build-package-data.mk	2010-05-24 19:38:07.000000000 +0200
@@ -42,6 +42,14 @@
 $1_$2_CONFIGURE_OPTS += --configure-option=--with-iconv-libraries="$$(ICONV_LIB_DIRS)"
 endif
 
+ifneq "$$(GMP_INCLUDE_DIRS)" ""
+$1_$2_CONFIGURE_OPTS += --configure-option=--with-gmp-includes="$$(GMP_INCLUDE_DIRS)"
+endif
+
+ifneq "$$(GMP_LIB_DIRS)" ""
+$1_$2_CONFIGURE_OPTS += --configure-option=--with-gmp-libraries="$$(GMP_LIB_DIRS)"
+endif
+
 ifeq "$3" "0"
 $1_$2_CONFIGURE_OPTS += $$(BOOT_PKG_CONSTRAINTS)
 endif