Found with J2SE 1.5.0 FCS (b64).

Steps to reproduce:
- generate key using
  keytool -genkey -alias MyAlias -keystore ./keystore
  type in infos for dname and choose some passwords
- list the keys (optional)
  keytool -list -keystore ./keystore
- try to clone key
  keytool -keyclone -alias MyAlias -keystore ./keystore
  you will be prompted for keystore password which passes OK, then for key
  password which fails. See "conversation" bellow.

jt146064@sr-eprg05-01:~/tmp/keytooltest>java -version
java version "1.5.0"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-b64)
Java HotSpot(TM) Server VM (build 1.5.0-b64, mixed mode)
jt146064@sr-eprg05-01:~/tmp/keytooltest>which java
/home/jt146064/java/bin/java
jt146064@sr-eprg05-01:~/tmp/keytooltest>which keytool
/home/jt146064/java/bin/keytool
jt146064@sr-eprg05-01:~/tmp/keytooltest>keytool -genkey -alias MyAlias -keystore ./keystore
Enter keystore password: jt146064
What is your first and last name?
  [Unknown]: Jiri Tusla
What is the name of your organizational unit?
  [Unknown]: G11n
What is the name of your organization?
  [Unknown]: SMI
What is the name of your City or Locality?
  [Unknown]: Prague
What is the name of your State or Province?
  [Unknown]: Czech Rep.
What is the two-letter country code for this unit?
  [Unknown]: CZ
Is CN=Jiri Tusla, OU=G11n, O=SMI, L=Prague, ST=Czech Rep., C=CZ correct?
  [no]: yes

Enter key password for <MyAlias>
        (RETURN if same as keystore password): prague_g11n
jt146064@sr-eprg05-01:~/tmp/keytooltest>keytool -list -keystore ./keystore
Enter keystore password: jt146064

Keystore type: jks
Keystore provider: SUN

Your keystore contains 1 entry

myalias, Oct 13, 2004, keyEntry,
Certificate fingerprint (MD5): 49:DB:62:B6:79:D6:97:61:C9:11:23:B0:0B:1D:B5:2F
jt146064@sr-eprg05-01:~/tmp/keytooltest>keytool -keyclone -alias MyAlias -dest SCTAlias -keystore ./keystore
Enter keystore password: jt146064
Enter key password for <MyAlias>prague_g11n
keytool error: java.security.UnrecoverableKeyException: Cannot recover key
jt146064@sr-eprg05-01:~/tmp/keytooltest>
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