diff --git a/lib/des/rctest.c b/lib/des/rctest.c
index 52baa0944..5b301b9a8 100644
--- a/lib/des/rctest.c
+++ b/lib/des/rctest.c
@@ -96,7 +96,7 @@ static unsigned char plain3[] =
 	0x20, 0x2d, 0x20, 0x45, 0x69, 0x6e, 0x6f, 0x20,
 	0x4c, 0x65, 0x69, 0x6e, 0x6f };
       
-const char key3[16] = 
+static unsigned char key3[16] = 
     { 0x29, 0x04, 0x19, 0x72, 0xfb, 0x42, 0xba, 0x5f,
       0xc7, 0x12, 0x77, 0x12, 0xf1, 0x38, 0x29, 0xc9 };