wcf error

I have saved the data in local database in the WP7 . I have a Task table there . There may be 10,15,20 or... rows of data in that table . I want to send those number of rows of data to server using my wcf service . I am able to send the parameter to the server like i have a login method in the wcf which takes email and password as parameter returns boolean value true or false. Now I need to send these few 10,15,20 or... rows of data to the server via the WCF service and save in the server database. I am stuck at sending the number of rows to the wcf method. I have the Task data in list object. I have debugged and checked the presence of data.
Here is the code part

using (dbContext context = new dbContext())
{
IQueryable taskStatQuery = from t in context.Tasks select t;
List allTasksStatus = taskStatQuery.ToList();
WcfFSMSer.Win7MobileServiceClient client = new WcfFSMSer.Win7MobileServiceClient();
client.TestFunctionAsync(whatParamToSendForSendingFewRows);
client.TestFunctionCompleted +=
new EventHandler(client_TestFunctionCompleted);
}
void client_TestFunctionCompleted(object sender, WcfFSMSer.TestFunctionCompletedEventArgs e)
{ }
I am able to get all tasks list in this variable List allTasksStatus.
 How to send these values from WP7 to WCF?
Thanks in advance