Added a dependency on mpfr.

Makefile.am

@@ -281,7 +281,7 @@ PYLIBS  = ledger_util ledger_math ledger_expr \
 	  ledger_data ledger_parse	      \
 	  ledger_report ledger_extra	      \
 	  ledger_python			      \
-	  gmp				      \
+	  gmp mpfr			      \
 	  boost_system$(BOOST_SUFFIX)	      \
 	  boost_date_time$(BOOST_SUFFIX)      \
           boost_filesystem$(BOOST_SUFFIX)     \

configure.ac

@@ -109,6 +109,25 @@ else
   AC_MSG_FAILURE("Could not find gmp library (set CPPFLAGS and LDFLAGS?)")
 fi
 
+# check for mpfr
+AC_CACHE_CHECK(
+  [if libmpfr is available],
+  [libmpfr_avail_cv_],
+  [libmpfr_save_libs=$LIBS
+   LIBS="-lmpfr $LIBS"
+   AC_LANG_PUSH(C++)
+   AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <mpfr.h>]], [[mpfr_t bar;
+      mpfr_init(bar);
+      mpfr_clear(bar);]])],[libmpfr_avail_cv_=true],[libmpfr_avail_cv_=false])
+   AC_LANG_POP
+   LIBS=$libmpfr_save_libs])
+
+if [test x$libmpfr_avail_cv_ = xtrue ]; then
+  LIBS="-lmpfr $LIBS"
+else
+  AC_MSG_FAILURE("Could not find mpfr library (set CPPFLAGS and LDFLAGS?)")
+fi
+
 # check for boost_regex
 AC_CACHE_CHECK(
   [if boost_regex is available],

src/system.hh

@@ -121,6 +121,7 @@ typedef std::ostream::pos_type ostream_pos_type;
 #endif
 
 #include <gmp.h>
+#include <mpfr.h>
 #include "SHA1.h"
 
 #include "irrXML.h"		// XML parser