During my current project, I had the possibility to use Ajax to extend some textbox functionalities in one of the web parts that were being developed.
Visual Studio 2008 does a good job in modifying the web.config automatically, but when the project is finished, there’s the need to put all the code into test, pre production and production. Manual changes to the web.config for the Ajax bits were not an option.
After some research on Internet, and a couple of failed attempts, I found a very good STSADM command extension at Codeplex called Ajaxify MOSS.
This STSADM extension deploys changes to the Web Application’s web.config for both Ajax 1.6 and Ajax 3.5.
One catch, at least one site collection needs to be present in order to be able to use the STSADM extension.