diff --git a/programs/pkey/dh_genprime.c b/programs/pkey/dh_genprime.c
index 72a2916..840a569 100644
--- a/programs/pkey/dh_genprime.c
+++ b/programs/pkey/dh_genprime.c
@@ -49,7 +49,7 @@
     havege_state hs;
     FILE *fout;
 
-    mpi_init( &G, &P, &Q, NULL );
+    mpi_init( &G ); mpi_init( &P ); mpi_init( &Q );
     mpi_read_string( &G, 10, GENERATOR );
 
     printf( "\n  . Seeding the random number generator..." );
@@ -113,7 +113,7 @@
 
 exit:
 
-    mpi_free( &Q, &P, &G, NULL );
+    mpi_free( &G ); mpi_free( &P ); mpi_free( &Q );
 #else
     printf( "\n  ! Prime-number generation is not available.\n\n" );
 #endif