state on running webservice

[Mr. x]

Hello,
I am using webservice with success,
but the webservice function I use do some query on database, and it takes
about 0.5 seconds.
On client I can call the webservice function a lot of times,
and when I do this fast (less then 0.5 seconds interval),
I get the message : "something else fire the event" (if I use the standard
webservice.htc, and standard onWSResult.

Here is onWSresult :

function onWSresult()
{
if((event.result.error)&&(iCallID==event.result.id))
{
// Pull the error information from the event.result.errorDetail
properties
var xfaultcode = event.result.errorDetail.code;
var xfaultstring = event.result.errorDetail.string;
var xfaultsoap = event.result.errorDetail.raw;
alert(event.result.errorDetail.string);
// Add code to handle specific error codes here
}
// if there was no error, and the call came from the call() in init()
else if((!event.result.error) && (iCallID == event.result.id))
{
// Show the arithmetic!
showRes(event.result.value);
}
else
{
alert("Something else fired the event!");
}
}

.... I think that webservice acts like thread and there is a state that
webservice is already running.
How can I find that state ?

Thanks