trying to run a python script on AWS Lambda, but Lambda fails if I load a virtualenv directory

I've got a script working running on AWS Lambda that will run a python script, however I need boto installed, so I have created a virtualenv.

However if I pass the env/* directories to Lambda, it just fails with a system error.

I have ziped and passed the directory and then just done an ls to see if its there, but it still fails. Somehow Lambda is unhappy with the env/* directory, either size or some rule, not sure. Its not the python script failing, just loading the env/* causes the failure.

Can anyone tell me why, or how to get around it

Thanks

Marc Nealer