Here's a section of the actual code piece, and the output of all 
involved variables after the routine.

CODE::
<?php
Namespace xBB\Database;
require_once('./Core/Database/EntityQueries.class.php');

class UserQueries extends EntityQueries
{
	public function Fill($User, Array &$Data)
	{
		parent::Fill($User, $Data);
		$User->Password	= $Data['Password'];
		$User->LastLogin	= $Data['LastLogin'];
		$User->LastIp	= $Data['LastIp'];

		require_once('./Core/Entities/Profile.class.php');
		$User->Profile		= new 
\xBB\Entities\Profile();
		$User->Profile->UserId	= $Data['EntityId'];

		$this->Database->Profiles->Fill($User->Profile, 
$Data);
		if(sizeof($Data)>1){
		die(print_r($User).print_r($User-
>Profile).print_r($Data));
		}
	}
...


OUTPUT::
xBB\Entities\User Object ( [Password] => [LastLogin] => [Profile] => 
xBB\Entities\Profile Object ( [UserId] => [FirstName] => [MiddleName] 
=> [LastName] => [Avatar] => [Alias] => [Gender] => [Signature] => ) 
[LastIp] => [EntityId] => [Name] => [Description] => [Updated] => 
[Created] => [Parent] => [Owner] => ) xBB\Entities\Profile Object ( 
[UserId] => [FirstName] => [MiddleName] => [LastName] => [Avatar] => 
[Alias] => [Gender] => [Signature] => ) Array ( [EntityId] => 
USER_4974b612242741.58553835 [Password] => test [LastLogin] => 
[LastIp] => [Name] => test [Description] => [Updated] => [Created] => 
2009-01-19 17:19:14 [Parent] => [Owner] => [UserId] => 
USER_4974b612242741.58553835 [FirstName] => [MiddleName] => 
[LastName] => [Avatar] => [Alias] => [Gender] => [Signature] => ) 
111Page Generation Time:: 0.093775 seconds

It also seems that if I set the values in the object manually - in 
the above example, $User->Password = 'notest', then the property is 
set. If I do the same to the array $Data, $Data['Password'] = 
'notest', It does not set the existing Password index, rather it 
creates a second Password index, which is shown in print_r below.

Array ( [EntityId] => USER_4974b612242741.58553835 [Password] => test 
[LastLogin] => [LastIp] => [Name] => test [Description] => [Updated] 
=> [Created] => 2009-01-19 17:19:14 [Parent] => [Owner] => [UserId] 
=> USER_4974b612242741.58553835 [FirstName] => [MiddleName] => 
[LastName] => [Avatar] => [Alias] => [Gender] => [Signature] => 
[Password] => notest ) 111Page Generation Time:: 0.09224 seconds

A single array with two "Password" entries...strange, yes? =)

I've found a workaround for this problem.

Using extract($Data) I was able to assign $User->Password to the 
resulting $Password variable and get the correct value in place.

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