Impersonation and Unhandled Communication Fault occurred

Hi,

This is the code of Project server 2007 and trying to make it run inside the 2010, for impersonating a user and Approve the submitted task for the user automatically.

Following is my Code

while reading the submitted data I am getting this Error "Unhandled Communication Fault occurred"

ResourceDerived resProxyBySSP = new ResourceDerived();
            StatusingDerived statsProxyBySSP = new StatusingDerived();
            System.Net.NetworkCredential mycred = new System.Net.NetworkCredential("epm.admin", "password", "Domainname");

            bool isWinUser = true;
            string username = "Domain\\ABC";
            Guid userId = new Guid("D6AAD44B-93CF-4F76-BC2D-19704D455247");
            Guid siteid = new Guid("81DC8139-7E5A-41EF-BB5A-2CFA1316B24F");

            resProxyBySSP.Url = PROJECTSERVER_WIN_URL + "resource.asmx";
            resProxyBySSP.Credentials = mycred;

            ResourceDerived.SetImpersonationContext(isWinUser, username, userId, Guid.Empty, siteid, "1033");
            //Guid ImpersonateUserID = resProxyBySSP.GetCurrentUserUid();

            statsProxyBySSP.Url = PROJECTSERVER_WIN_URL + "statusing.asmx"; ;
            statsProxyBySSP.Credentials = mycred;

            StatusingDerived.SetImpersonationContext(isWinUser, username, userId, Guid.Empty, siteid, "1033");
            StatusApprovalDataSet SAD = statsProxyBySSP.ReadStatusApprovalsSubmitted(false);

            for (int j = 0; j < SAD.StatusApprovals.Count; j++)
            {
                SAD.StatusApprovals[j].ASSN_TRANS_ACTION_ENUM = 1;
                break;
            }
            statsProxyBySSP.UpdateStatusApprovals(SAD);
            statsProxyBySSP.QueueApplyStatusApprovals(Guid.NewGuid(), "");

Thanks, Parth