[fw-general] pre-validating files in Zend_File_Transfer

[Wilson Revehl (Go Media Inc.)]

Hello ZF'ers. I'm digging the simplicity of Zend_File_Transfer but ran into 
something I'm not quite sure how to tackle. I want to avoid having extension 
and mime exceptions in both javascript and php so I'm hoping to keep file 
validation on the server. But I don't want users to have to wait for their 
whole file to upload only to find out they weren't allowed to upload that file 
type in the first place. It seems like the receive() method mainly serves the 
purpose of accepting the file into the setDirectory. But that the file is still 
uploaded into temporary space.
Is it possible for me to use the lovely File_Transfer validators in conjunction 
with a function to stop the files in their tracks if they fail? I want to make 
this as resource efficient as possible for both the client and the server. 
Thank you very much for any insight on this!
Also, are there any handy chunking/streaming options I'm not seeing?
-Wilson