diff -ur groff-1.18.orig/contrib/mom/Makefile.sub groff-1.18/contrib/mom/Makefile.sub
--- groff-1.18.orig/contrib/mom/Makefile.sub	2002-06-07 13:56:32.000000000 +0200
+++ groff-1.18/contrib/mom/Makefile.sub	2002-08-06 13:25:29.000000000 +0200
@@ -23,7 +23,7 @@
   $(top_builddir)/src/devices/grops
 groff_bin_path=`echo $(groff_bin_dirs) | sed -e 's| \+|:|g'`
 
-FFLAG=-F$(top_builddir)/font
+FFLAG=-F$(top_builddir)/font -F$(top_srcdir)/font
 TFLAG=-M$(top_builddir)/tmac -M$(srcdir)
 
 GROFF=GROFF_BIN_PATH=$(groff_bin_path); \