--- a/liboctave/ColVector.cc
+++ b/liboctave/ColVector.cc
@@ -31,6 +31,39 @@
 #include "Matrix.h"
 #include "mx-inlines.cc"
 #include "lo-error.h"
+#include "f77-uscore.h"
+
+// Fortran functions we call.
+
+extern "C"
+{
+  int F77_FCN (dgemm) (const char*, const char*, const int*,
+		       const int*, const int*, const double*,
+		       const double*, const int*, const double*,
+		       const int*, const double*, double*, const int*,
+		       long, long);
+
+/*
+ * f2c translates complex*16 as
+ *
+ *   typedef struct { doublereal re, im; } doublecomplex;
+ *
+ * and Complex.h from libg++ uses
+ *
+ *   protected:
+ *     double re;
+ *     double im;
+ *
+ * as the only data members, so this should work (fingers crossed that
+ * things don't change).
+ */
+
+  int F77_FCN (zgemm) (const char*, const char*, const int*,
+		       const int*, const int*, const Complex*,
+		       const Complex*, const int*, const Complex*,
+		       const int*, const Complex*, Complex*, const int*,
+		       long, long);
+}
 
 /*
  * Column Vector class.