Read This If You Have an EMC Celerra or VNX and OSX Lion Clients! Jason Nash?s Blog:

If you have an EMC Celerra or VNX and there is any chance a user will connect to a CIFS share from an Apple computer running OSX 10.7 (Lion) you should read this EMC Technical Advisory. Lion can cause the Data Movers to panic and reboot which will initiate a DM failover.

Rife in the enterprise but far from ready.

EDIT: CIFS=DM=NAS, corrected title thanks to @thechads