在salesforce.com Flex应用程序中，如何在运行时内省字段？

I have a requirement I'm fairly stuck on and wonder if anyone has any suggestions. I am building a salesforce flex application that needs to be able to connect to different salesforce domains. Upon connect, I need to get a list of available objects and their fields. From there I need to parse those fields into a series of components (lablels, data, etc). I'm having trouble finding how to get a list of all available objects and fields upon connection to an domain, does anyone have any experience here?I have a requirement I'm fairly stuck on and wo