Redirecting home folder to win 2003 user network folder

I'm baffled and have scoured the ends of the internet for this info.

Here's my situation:

- Running Win 2003 server throughout a school, all staff has working network accounts

- Brand new Mac lab put in, plus cart of 28 macbook pros ( all on OSX Lion)

- authenticating to AD fine, users are logging into network accounts

- each user needs to be able to access their network drive folder.

- setting each user up individually to map their folder isn't an option, there are over 300 accounts!

- optimal result: to have the user's home folder redirected their network folder on the win 2003 server

- not using an OSX server at all in this configuration, and no budget to get one

So, any ideas how to make this work? We want to make it so anyone can log onto ANY computer - mac or pc - and be able to read/write to their documents/files over the network.

Much thanks in advance for any help!

 

Update:

After discussion with the purchasing powers that be, we are going to invest and get the Lion Server app ($50) and install it on the teacher station in the computer lab. Hopefully, this will help us integrate our macs with our Windows network.