diff --git a/lib/des/Makefile.am b/lib/des/Makefile.am
index 1bd0f8208..26c62f194 100644
--- a/lib/des/Makefile.am
+++ b/lib/des/Makefile.am
@@ -118,12 +118,8 @@ libhcrypto_la_SOURCES =	\
 imathsource =			\
 	imath/imath.c		\
 	imath/imath.h		\
-	imath/imrat.c		\
-	imath/imrat.h		\
 	imath/iprime.c		\
-	imath/iprime.h		\
-	imath/rsamath.c		\
-	imath/rsamath.h
+	imath/iprime.h
 
 $(libhcrypto_la_OBJECTS): hcrypto-link
 
diff --git a/lib/des/imath/import.sh b/lib/des/imath/import.sh
index 1349f7000..6fca6ae23 100644
--- a/lib/des/imath/import.sh
+++ b/lib/des/imath/import.sh
@@ -11,6 +11,8 @@ fi
 rm *.[ch]
 
 headers=`grep ^HDRS "$dir"/Makefile |sed 's/^HDRS=//' | sed 's/imdrover.h//'`
+code=`echo $headers | sed 's/imrat.h//g'`
+code=`echo $headers | sed 's/rsamath.h//g'`
 code=`echo $headers | sed 's/\.h/.c/g'`
 
 for a in $headers $code LICENSE ; do