ScriptMethod problems with Mono and FastCGI/Nginx

I'm p开发者_StackOverfloworting a .Net application to Mono running via FastCGI on Nginx and generally everything is going swell.

ScriptMethods/WebMethods are not working however -- they throw a 500:

System.Web.HttpException: Method POST is not allowed when accessing file /site/path/widget/editwidgets.aspx/SaveLayout

Switching to [ScriptMethod(UseHttpGet=true)] doesn't help and just leads to other problems.

What am I missing here? I've seen what I think is a solution for lighttpd (mapping all .Net extensions to .aspx -- though I'm not sure why that would work -- it certainly appears that Mono is handling the request).

I'm porting several app's also and ScriptMethod/PageMethod is a pain. This shows a solution that I use.