Ok, after all the problems and wrangling trying to get CIFS shares to work reliably with OSX Lion (problems writing to CIFS shares, mainly error 50 etc…). I’ve installed napp-it on the server along with netatalk (there is a default netatalk install in the napp-it howto on the site). I turned off all the SMB/CIFS, iSCSI, and NFS shares (except what I need for my Winderz friends) and moved all my shares to AFP.
Since Lion will no longer let you use USB drives connected to an Airport Extreme I had to come up with something (I had wrestled with trying to set up time machine on iSCSI, but issues with compatibility from old iSCSI initiators and the cost of the new ones drove me away). So far everything works perfectly, even time machine.
I may post howto’s but since napp-it is reasonably easy to use (a little clunky, but everything is there) I will wait until I see some questions here before I go to the trouble.