diff --git a/src/share/classes/sun/security/tools/KeyTool.java b/src/share/classes/sun/security/tools/KeyTool.java
index a3aa50f435d4f031262884af10b619b5f6079daa..163e78fc5cfe58194b9b21c670043251594ef313 100644
--- a/src/share/classes/sun/security/tools/KeyTool.java
+++ b/src/share/classes/sun/security/tools/KeyTool.java
@@ -1072,8 +1072,8 @@ public final class KeyTool {
 
         X509CertInfo info = new X509CertInfo();
         info.set(X509CertInfo.VALIDITY, interval);
-        info.set(X509CertInfo.SERIAL_NUMBER, new CertificateSerialNumber
-                 ((int)(firstDate.getTime()/1000)));
+        info.set(X509CertInfo.SERIAL_NUMBER, new CertificateSerialNumber(
+                    new java.util.Random().nextInt() & 0x7fffffff));
         info.set(X509CertInfo.VERSION,
                      new CertificateVersion(CertificateVersion.V3));
         info.set(X509CertInfo.ALGORITHM_ID,
@@ -2121,8 +2121,8 @@ public final class KeyTool {
         certInfo.set(X509CertInfo.VALIDITY, interval);
 
         // Make new serial number
-        certInfo.set(X509CertInfo.SERIAL_NUMBER, new CertificateSerialNumber
-                     ((int)(firstDate.getTime()/1000)));
+        certInfo.set(X509CertInfo.SERIAL_NUMBER, new CertificateSerialNumber(
+                    new java.util.Random().nextInt() & 0x7fffffff));
 
         // Set owner and issuer fields
         X500Name owner;
diff --git a/src/share/classes/sun/security/x509/CertAndKeyGen.java b/src/share/classes/sun/security/x509/CertAndKeyGen.java
index 38ca600927b63594064ecb6771848f12edcbef6e..2cf34c871ec733e1b12eb0187c6c69b97c3a0aa7 100644
--- a/src/share/classes/sun/security/x509/CertAndKeyGen.java
+++ b/src/share/classes/sun/security/x509/CertAndKeyGen.java
@@ -265,8 +265,8 @@ public final class CertAndKeyGen {
             // Add all mandatory attributes
             info.set(X509CertInfo.VERSION,
                      new CertificateVersion(CertificateVersion.V3));
-            info.set(X509CertInfo.SERIAL_NUMBER,
-                 new CertificateSerialNumber((int)(firstDate.getTime()/1000)));
+            info.set(X509CertInfo.SERIAL_NUMBER, new CertificateSerialNumber(
+                    new java.util.Random().nextInt() & 0x7fffffff));
             AlgorithmId algID = issuer.getAlgorithmId();
             info.set(X509CertInfo.ALGORITHM_ID,
                      new CertificateAlgorithmId(algID));