Script Manager required error message and another issue with Telerik versions

[Bill]

Can someone help me with a problem.
Actually 2 problems...
The first one is Telerik related but maybe not a Telerik issue per-se
I am using Telerik Telerik.Web.UI.dll Version 2010.3.1317.40 on a DotNetNuke 04.09.05 website
http://Sarvac.ca

On any page using modules I create with Ajax, I get an error that I need to have an Ajax Script Manager on the page.
Adding one does not help.
I don't know why I get that error because I never needed one before because in the DotNetNuke host settings there is an option for Use Ajax and in the module settings a checkbox for Allow Prerendering .
Also, on my Dev server (IIS 7, Windows 7) it works fine- same site files and same web.config but no error.

I get around this by adding the Telerik Script manager and the Telerik Ajax manager and all is OK but...
For my own modules I created I don't mind doing this but for 3rd party modules which I dont have the source code for, it is a problem.

Does anyone know of something that could be different that would cause this issue?
On the prod server that I get the error, it is Windows Server 2003, IIS 6

Second issue:
How do you handle requirements to use 2 different versions of Telerik dll at same time.

This is regarding 3rd party 'Rezults' module I installed from OnyakTech which use an older version of Telerik than I use.
Heres what happenned:
- Uninstalled Onyaktech library
- It also removed Telerik DLL which I need for modules I created
- I replaced the Telerik DLL- OK
- Reinstalled Library- no errors
- Tested the OnyakTech Rezults module- seemed to work OK now
- Replaced the Telerik DLL with newer version
- Rezults broken again.
 " Could not load file or assembly 'Telerik.Web.UI, Version=2009.3.1103.20 "

[Bill]

Looks like I got around the second problem by adding this to Web.config

<assemblyBinding......................................>


  [Line removed]

<dependentAssembly>

<assemblyIdentity name="Telerik.Web.UI" publicKeyToken="121fae78165ba3d4" culture="neutral" />
<bindingRedirect oldVersion="2009.3.1103.20" newVersion="2010.3.1317.40" />

</dependentAssembly>

</assemblyBinding>

[Kiara]

The ajax-enabled pages require asp ScriptManager or ScriptManagerProxy (in content pages or user controls for the latter) and this is not related to telerik. Their ScriptManager works with ScriptManagerProxy and you can use it as a substitute of the default asp SciprtManager if needed, Bill.

The bindingRedirect in web.config is the best fit to reference new versions of the telerik controls without further hassle.

Kiara 

[Bill]

Yes I realize that but supposedly DotNetNuke adds it automatically.
It works fine on Dev as is

Something is different between the 2 boxes.