public static string GetSSPConnectionString(SPWebApplication webApp)
{
    try
    {
        ServerContext serverContext = ServerContext.GetContext(webApp);

        Type serverContextType = serverContext.GetType();
        // Get the value of the field m_ServerFarm;                
        SPPersistedObject serverFarm = (SPPersistedObject)serverContextType.
        GetField("m_ServerFarm", BindingFlags.Instance | BindingFlags.NonPublic).
        GetValue(serverContext);
        // Now we need to retrieve a collection of all the Shared Services Providers
        // public SharedResourceProviderCollection SharedResourceProviders { get; }
        PropertyInfo sharedSerivesProvidersProperty = serverFarm.GetType().
        GetProperty("SharedResourceProviders");
        IEnumerable sharedServicesProviders = (IEnumerable)
        sharedSerivesProvidersProperty.GetValue(serverFarm, null);

        Type sharedServiceProviderType = Assembly.GetAssembly(serverContextType).
        GetType("Microsoft.Office.Server.Administration.SharedResourceProvider");
        PropertyInfo webApplicationsProperty = sharedServiceProviderType.
        GetProperty("WebApplications");

        object serviceDB=null;
        foreach (SPPersistedObject sharedSericeProvider in sharedServicesProviders)
        {
            IEnumerable webApplications = (IEnumerable)webApplicationsProperty.
            GetValue(sharedSericeProvider, null);
            // Iterate through all the web applications associated with the current SSP.
            foreach (SPWebApplication webAppAssociatedWithSSP in webApplications)
            {
                if (webApp.Id == webAppAssociatedWithSSP.Id)
                {
                    serviceDB = sharedSericeProvider.GetType().GetProperty
                    ("ServiceDatabase").GetValue(sharedSericeProvider, null);
                    return ((Microsoft.SharePoint.Administration.SPDatabas(serviceDB)).
                    DatabaseConnectionString);                
                }
            }                    
        }
        return String.Empty;                  
    }
    catch (Exception ex)
    {
        ReportsLogger.GetInstance().LogException(ex);
        return String.Empty;
    }
    finally
    {
        ReportsLogger.GetInstance().Debug("Exiting method");
    }

}