Program: 103618
Project: 103618
Buggy source:
/** 
 * Saves the user input when the "Next" wizard buttons is clicked.
 * @param registration the SIPAccountRegistration
 */
public void commitPage(SIPAccountRegistration registration){
  String userID=null;
  char[] password=null;
  String serverAddress=null;
  String proxyAddress=null;
  if (accountPanel.isCreateAccount()) {
    NewAccount newAccount=getCreateAccountService().createAccount();
    if (newAccount != null) {
      userID=newAccount.getUserName();
      password=newAccount.getPassword();
      serverAddress=newAccount.getServerAddress();
      proxyAddress=newAccount.getProxyAddress();
      if (serverAddress == null)       serverAddress=setServerFieldAccordingToUIN(userID);
      if (proxyAddress == null)       proxyAddress=serverAddress;
    }
 else {
      return;
    }
  }
 else {
    userID=accountPanel.getUserID();
    password=accountPanel.getPassword();
    serverAddress=connectionPanel.getServerAddress();
    proxyAddress=connectionPanel.getProxy();
  }
  if (userID == null || userID.trim().length() == 0)   throw new IllegalStateException("String_Node_Str");
  registration.setUserID(userID);
  if (password != null)   registration.setPassword(new String(password));
  registration.setRememberPassword(accountPanel.isRememberPassword());
  registration.setServerAddress(serverAddress);
  registration.setProxy(proxyAddress);
  String displayName=accountPanel.getDisplayName();
  registration.setDisplayName(displayName);
  String authName=connectionPanel.getAuthenticationName();
  if (authName != null && authName.length() > 0)   registration.setAuthorizationName(authName);
  registration.setServerPort(connectionPanel.getServerPort());
  registration.setProxyPort(connectionPanel.getProxyPort());
  registration.setPreferredTransport(connectionPanel.getSelectedTransport());
  registration.setEnablePresence(presencePanel.isPresenceEnabled());
  registration.setForceP2PMode(presencePanel.isForcePeerToPeerMode());
  registration.setDefaultEncryption(connectionPanel.isDefaultEncryptionEnabled());
  registration.setSipZrtpAttribute(connectionPanel.isSipZrtpEnabled());
  registration.setPollingPeriod(presencePanel.getPollPeriod());
  registration.setSubscriptionExpiration(presencePanel.getSubscriptionExpiration());
  registration.setKeepAliveMethod(connectionPanel.getKeepAliveMethod());
  registration.setKeepAliveInterval(connectionPanel.getKeepAliveInterval());
  SIPAccRegWizzActivator.getUIService().getAccountRegWizardContainer().setBackButtonEnabled(true);
}

Fixed version (ground truth):
/** 
 * Saves the user input when the "Next" wizard buttons is clicked.
 * @param registration the SIPAccountRegistration
 */
public boolean commitPage(SIPAccountRegistration registration){
  String userID=null;
  char[] password=null;
  String serverAddress=null;
  String proxyAddress=null;
  if (accountPanel.isCreateAccount()) {
    NewAccount newAccount=getCreateAccountService().createAccount();
    if (newAccount != null) {
      userID=newAccount.getUserName();
      password=newAccount.getPassword();
      serverAddress=newAccount.getServerAddress();
      proxyAddress=newAccount.getProxyAddress();
      if (serverAddress == null)       serverAddress=setServerFieldAccordingToUIN(userID);
      if (proxyAddress == null)       proxyAddress=serverAddress;
    }
 else {
      return false;
    }
  }
 else {
    userID=accountPanel.getUserID();
    password=accountPanel.getPassword();
    serverAddress=connectionPanel.getServerAddress();
    proxyAddress=connectionPanel.getProxy();
  }
  if (userID == null || userID.trim().length() == 0)   throw new IllegalStateException("String_Node_Str");
  registration.setUserID(userID);
  if (password != null)   registration.setPassword(new String(password));
  registration.setRememberPassword(accountPanel.isRememberPassword());
  registration.setServerAddress(serverAddress);
  registration.setProxy(proxyAddress);
  String displayName=accountPanel.getDisplayName();
  registration.setDisplayName(displayName);
  String authName=connectionPanel.getAuthenticationName();
  if (authName != null && authName.length() > 0)   registration.setAuthorizationName(authName);
  registration.setServerPort(connectionPanel.getServerPort());
  registration.setProxyPort(connectionPanel.getProxyPort());
  registration.setPreferredTransport(connectionPanel.getSelectedTransport());
  registration.setEnablePresence(presencePanel.isPresenceEnabled());
  registration.setForceP2PMode(presencePanel.isForcePeerToPeerMode());
  registration.setDefaultEncryption(connectionPanel.isDefaultEncryptionEnabled());
  registration.setSipZrtpAttribute(connectionPanel.isSipZrtpEnabled());
  registration.setPollingPeriod(presencePanel.getPollPeriod());
  registration.setSubscriptionExpiration(presencePanel.getSubscriptionExpiration());
  registration.setKeepAliveMethod(connectionPanel.getKeepAliveMethod());
  registration.setKeepAliveInterval(connectionPanel.getKeepAliveInterval());
  SIPAccRegWizzActivator.getUIService().getAccountRegWizardContainer().setBackButtonEnabled(true);
  return true;
}