Hilarious language in Apple Knowledge Base article
7. Connecting to (mounting) two or more SMB volumes simultaneously may cause a kernel panic.
The reason I found this is that I was looking how to transfer some files from my Mac to Windows XP. XP had a share that allowed Everyone Change rights (configured both in Sharing and in NTFS). OSX gave me an option to connect as Guest or provide username/password. Connecting as Guest did NOT work. I spent a few minutes looking online, but then decided to save time and just created a user and gave that user Change permissions on the share. Then OSX was able to connect.
Unrelated, but every time I see this it cracks me up: pay attention to Blue Screen of Depth that is used as a preview of PCs. I like developers with sense of humor.