(HTTP Error 500-Internal Server Error) when attempting to download doc from google doc api

Question

I am attempting to download a document from my google apps account using the Google Documents List Data API and when i attempt to download a document from the server I get an HTTP error code 500.

I am able to authenticate against the documents service using the clientLogin strategy. Using the token i can then search my document feed and retrieve document ids. I can even search for a specific document id using:

http://docs.google.com/feeds/documents/private/full/document:{doc id}

and find the document.

however, when i try:

http://docs.google.com/feeds/download/documents/Export?docID={doc id}&exportFormat=txt

i get the 500 error code. i have tried this with every valid value for exportFormat.

couple of things that might be of interest:
im using ruby to get and post to the urls directly
my account is a corporate HOSTED account and i authenticate as such

any insight would be greatly appreciated.