ASP.NET client-side validation working, but button click not working

Hello,

I have just copied a new site up to the production server and have encountered an odd problem. The site uses validation, and this seems to be working fine. For some reason, link button clicking works fine, but normal button clicking doesn't do anything.

To clarify, if the page contains...

<asp:LinkButton ID="lOK" Text="OK" OnClick="lOK_Click" RunAt="server" />
<asp:Button ID="bOK" OnClick="bOK_Click" Text="OK" RunAt="server" />

then clicking the first works as expected, but clicking the second doesn't do anything at all.

I suppose this is something to do with the client-side Javascript, but I'm not sure what. I have tried copying the aspnet_client files again, but this didn't help. This all works fine on my development server, which is running the identical OS, SP, etc.

Any ideas? TIA

--
Alan Silver
(anything added below this line is nothing to do with me)
.