problem with System.Web.UI.ICallbackEventHandler

[ThatsIT.net.au]

I have been using System.Web.UI.ICallbackEventHandler to make calls to the
server and return html strings, it has been working well. but today I set
the group policy to customize the user agent with the company name. Now I
realize that the call backs don't work on any computer with a customized
user agent.

Can any body confirm this or now why?
Or know how to work around this?

--
Dim Alan as ThatsIT.net.au.Staffmember = New ThatsIT.net.au.Staffmember
Alan.signature = "Thank You"
Dim you as NewsgroupReader = New NewsgroupReader
Response.Write Alan.signature.toString()
Response.Write you.getName()
__________________________________________