Tooltip problem after button event triggered.

Hi,
I'm having a problem with a project developed in ASP.NET. We are using the tooltip control (ASPNetToolTip.NET4).
The tooltips work fine until you press a button and then the tooltips are gone. The tooltips and controls are all created dynamically.
We use a function to disable all buttons after a button is pressed to stop multiple transactions occurring. We originally thought this was the problem why the tooltips weren't displaying after a button press event. (The disableAll function which disables the buttons is called in the form onsubmit event)
But after playing around with the problem we managed to get the tooltips working, but the display flickers from time to time.
The code we used to get the tooltips showing again was the following in the code behind page:

if (!theForm.onsubmit || (theForm.onsubmit() != false)) {
theForm.__EVENTTARGET.value = eventTarget;
theForm.__EVENTARGUMENT.value = eventArgument;
theForm.submit();
}


We currently use our own postback which overrides the original. This is how it looks with the code above included (See below).

function MyDoPostBack(eventTarget, eventArgument) {
AllowDisableInputs = true
if (eventArgument.indexOf('trviewresource') >= 0)
AllowDisableInputs = false;

oldPostBack(eventTarget, eventArgument);
if (!theForm.onsubmit || (theForm.onsubmit() != false)) {
theForm.__EVENTTARGET.value = eventTarget;
theForm.__EVENTARGUMENT.value = eventArgument;
theForm.submit();
}

}

Our current problem is:
If we place the BOLD coding below 'oldPostBack(eventTarget, eventArgument);' the tooltips work but we get a flicker when the page is rendered.
If we place the BOLD coding just above 'oldPostBack(eventTarget, eventArgument);' then buttons never become re-enabled after being disabled.
I'm not sure why the BOLDED code fixed the problem we are having with the tooltips or why we have the occasional flicker. Any help would be appreciated.