Link existing resource to Active Directory

Question

I am working with an existing implementation of Project Server 2010 where Active Directory is used to synchronize resources.  When initially implementing this environment, it was decided that most people in the department would be created as resources,
however, they would not be given the "logon to Project Server" permission (they were created manually).  There have been some cases where these existing resources have later needed to have access to the server, so they are added to the necessary
AD group, and synchronized into Project Server.  Due to the existing account already being in the resource pool, it creates a 2nd resource with the same name but the windows user account tagged to the end (example, Jane Doe [DOMAIN\jdoe]). 
Is there any way to update the existing resource information so that Project Server knows to link that resource with the new resource in Active Directory?  We have tried manually selecting "logon to Project Server" and entering the windows
user ID, but it has the same behavior (adds a second resource to the enterprise resource pool). 
I understand that you can prevent active directory from synchronizing that account, but we are hoping there is a better solution that doesn't disable the inherant functionality of AD sync.
Thank you and let me know if you need additional information.

Answer 1

Which group you have mapped with Resource pool sync.
When you sync reosurce pool with AD in that case only resource will be added to the project server i mean to say :
The "logon to Project Server" button is unchecked
The Windows User Account is not  populated
The user is not added to the out of box Team Members security group
http://technet.microsoft.com/en-us/library/gg982985(v=office.14).aspx
 http://technet.microsoft.com/en-us/library/gg750243(v=office.14).aspx
these link will give you better idea.
For giving user permission you map project server group with AD groups this will give you proper access.
For resources you use resource pool sync .     
No Project Server user accounts will be automatically created for resources that are added to the Enterprise Resource Pool through Active
Directory synchronization.
If you go with 2nd approach you will not face any problem in future.
Once you do resource pool sync it will create reosurces without user login.
Then you can map Project Permission group with AD group it will add user account to the users who are present in ad. 
For this you have to create different- different groups in Ad as per project server group and add user as per your need in ad group. be careful do not t map project server group
with group which you are suing for resource pool mapping sync.  
kirtesh