In Security > Server Security > Encrypting Other Listeners for Unwired Server Defining Certificates for SSL Encryption, the note at the end of the task needs further information.
The note describes that a password change by keytool must match the password you configure in Sybase Control Center for SSL. However, the task neglects to mention that if you change the password, the password must also be applied to any alias that exists. You can do this with a keytool command similar to these examples:
keytool -keypasswd -alias sample1 -keypass changeit -new changeit2 -keystore keystore.jks
keytool -keypasswd -alias sample2 -keypass changeit -new changeit2 -keystore keystore.jks