Access denied on SPJobDefinition RunNow()

Recently I faced strange issue while executing a timer service through my web part. Since it was possible in MOSS 2007, but I know SharePoint 2010 does not support executing any timer job through code. I have already written a solution for setting up the property : RemoteAdministratorAccessDenied. This property allows modification of the SPPersistedObject from content web applications.  The post can be viewed at: http://www.directsharepoint.com/2011/04/access-denied-while-activating-feature.html. However when I tried to execute the timer, It gave an error as:

"Operation is not valid due to the current state of the object"

To resolve this, I cleared the HttpContext.Current property to null as:

SPSecurity.RunWithElevatedPrivileges(delegate()

                {

                    using (SPSite elevatedSite = new SPSite("Site URL"))

                    {

                        foreach (SPJobDefinition job in  elevatedSite.WebApplication.JobDefinitions)

                        {

                            if (job.Title.Equals("Your job name") && job.Status == SPObjectStatus.Online)

                            {

                                HttpContext.Current = null;

                                job.RunNow();

                                break;

                            }

                        }

                    }

                });