Hi,

The functionality of change password can be customized or modified by extending/ customizing the "Site Class"

Refer to the following link for more on this:-

http://www.salesforce.com/us/developer/docs/apexcode/Content/apex_classes_sites.htm

Code using "SiteControllerClass"


/**
 * An Apex class that creates a portal user
 */ 
    
public class SiteRegisterController {
    // PORTAL_ACCOUNT_ID is the account on which the contact will be created on  
    
    //  and then enabled as a portal user. 
    
    //Enter the account ID in place of <portal_account_id> below. 
    
    private static Id PORTAL_ACCOUNT_ID = '<portal_account_id>';
    
    public SiteRegisterController () {
    }

    public String username {get; set;}
    public String email {get; set;}
    public String password {get; set {password = value == null ? value : value.trim(); } }
    public String confirmPassword {get; set { confirmPassword = 
        value == null ? value : value.trim(); } }
    public String communityNickname {get; set { communityNickname = \
        value == null ? value : value.trim(); } }
      
    private boolean isValidPassword() {
        return password == confirmPassword;
    }
    
    public PageReference registerUser() {
        // If password is null, a random password is sent to the user 
    
        if (!isValidPassword()) {
           ApexPages.Message msg = new ApexPages.Message(ApexPages.Severity.ERROR, 
               Label.site.passwords_dont_match);
           ApexPages.addMessage(msg);
            return null;
        }    
        User u = new User();
        u.Username = username;
        u.Email = email;
        u.CommunityNickname = communityNickname;
        
        String accountId = PORTAL_ACCOUNT_ID;

        // lastName is a required field on user, but if it isn't specified,  
    
           the code uses the username
        String userId = Site.createPortalUser(u, accountId, password);
        if (userId != null) { 
            if (password != null && password.length() > 1) {
                return Site.login(username, password, null);
            }
            else {
                PageReference page = System.Page.SiteRegisterConfirm;
                page.setRedirect(true);
                return page;
            }
        }
        return null;
    }
    // Test method for verifying the positive test case 
    
    static testMethod void testRegistration() {
        SiteRegisterController controller = new SiteRegisterController();
        controller.username = 'test@force.com';
        controller.email = 'test@force.com';
        controller.communityNickname = 'test';
        // registerUser always returns null when the page isn't accessed as a guest user 
    
        System.assert(controller.registerUser() == null);
        controller.password = 'abcd1234';
        controller.confirmPassword = 'abcd123';
        System.assert(controller.registerUser() == null);
    }

}

The following is the Visualforce registration page that uses the SiteRegisterController Apex controller above:

<apex:page id="Registration" showHeader="false" controller="SiteRegisterController" standardStylesheets="true"> 
  <apex:outputText value="Registration"/>
  <br/>
  <apex:form id="theForm">
    <apex:messages id="msg" styleClass="errorMsg" layout="table" style="margin-top:1em;"/>
    <apex:panelGrid columns="2" style="margin-top:1em;">
      <apex:outputLabel value="{!$Label.site.username}" for="username"/>
      <apex:inputText required="true" id="username" value="{!username}"/>
      <apex:outputLabel value="{!$Label.site.community_nickname}" for="communityNickname"/>
      <apex:inputText required="true" id="communityNickname" required="true" value="{!communityNickname}"/>
      <apex:outputLabel value="{!$Label.site.email}" for="email"/>
      <apex:inputText required="true" id="email" required="true" value="{!email}"/>
      <apex:outputLabel value="{!$Label.site.password}" for="password"/>
      <apex:inputSecret id="password" value="{!password}"/>
      <apex:outputLabel value="{!$Label.site.confirm_password}" for="confirmPassword"/>
      <apex:inputSecret id="confirmPassword" value="{!confirmPassword}"/>
      <apex:outputText value=""/>
      <apex:commandButton action="{!registerUser}" value="{!$Label.site.submit}" id="submit"/>
    </apex:panelGrid>
  </apex:form>
cod</apex:page>

 Hope this gives you a clue....

Hi Ispita,

       Thanks for your reply.

        Can we capture the login credentials of the logged user.

Regards,

Phanikumar