diff --git a/bin/dnssec/dnssec-dsfromkey.c b/bin/dnssec/dnssec-dsfromkey.c
index 18fb64e901..9e152439b3 100644
--- a/bin/dnssec/dnssec-dsfromkey.c
+++ b/bin/dnssec/dnssec-dsfromkey.c
@@ -14,7 +14,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: dnssec-dsfromkey.c,v 1.11 2009/07/19 23:47:55 tbox Exp $ */
+/* $Id: dnssec-dsfromkey.c,v 1.12 2009/08/13 04:13:58 marka Exp $ */
 
 /*! \file */
 
@@ -367,7 +367,7 @@ main(int argc, char **argv) {
 			/* fall through */
 		case 'K':
 			dir = isc_commandline_argument;
-			if (strlen(dir) == 0)
+			if (strlen(dir) == 0U)
 				fatal("directory must be non-empty string");
 			break;
 		case 'f':
@@ -375,7 +375,7 @@ main(int argc, char **argv) {
 			break;
 		case 'l':
 			lookaside = isc_commandline_argument;
-			if (strlen(lookaside) == 0)
+			if (strlen(lookaside) == 0U)
 				fatal("lookaside must be a non-empty string");
 			break;
 		case 's':
diff --git a/bin/dnssec/dnssec-signzone.c b/bin/dnssec/dnssec-signzone.c
index 87eb60b495..a4fd2c7b0c 100644
--- a/bin/dnssec/dnssec-signzone.c
+++ b/bin/dnssec/dnssec-signzone.c
@@ -29,7 +29,7 @@
  * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: dnssec-signzone.c,v 1.225 2009/07/21 03:27:38 marka Exp $ */
+/* $Id: dnssec-signzone.c,v 1.226 2009/08/13 04:13:58 marka Exp $ */
 
 /*! \file */
 
@@ -3203,7 +3203,7 @@ main(int argc, char *argv[]) {
 
 		case 'd':
 			dsdir = isc_commandline_argument;
-			if (strlen(dsdir) == 0)
+			if (strlen(dsdir) == 0U)
 				fatal("DS directory must be non-empty string");
 			break;
 
diff --git a/bin/dnssec/dnssectool.c b/bin/dnssec/dnssectool.c
index df58ad3d24..32a8537438 100644
--- a/bin/dnssec/dnssectool.c
+++ b/bin/dnssec/dnssectool.c
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: dnssectool.c,v 1.49 2009/07/19 23:47:55 tbox Exp $ */
+/* $Id: dnssectool.c,v 1.50 2009/08/13 04:13:58 marka Exp $ */
 
 /*! \file */
 
@@ -293,7 +293,7 @@ strtotime(const char *str, isc_int64_t now, isc_int64_t base) {
 	const char *orig = str;
 	char *endp;
 
-	if (strlen(str) == 1 && (str[0] == '0' || str[0] == '-'))
+	if ((str[0] == '0' || str[0] == '-') && str[1] == '\0')
 		return ((isc_stdtime_t) 0);
 
 	if (strncmp(str, "now", 3) == 0) {