I'm going to take a quick guess and say that the network isn't up yet when your system tries to mount it. I have the same issue, but a quick "mount -a" after boot mounts it. Of course, I rarely shut my desktop off, so it's not often an issue. That's my guess at what's going on, anyway.
Sent from my Galaxy Nexus using Tapatalk
"Anybody who tells me I can't use a program because it's not open source, go suck on rms. I'm not interested. 99% of that I run tends to be open source, but that's _my_ choice, dammit." -- Linus Torvalds, 2004.