USB no proper work

Fri Aug 16 20:05:29 UTC 2013

uname -a
FreeBSD scorpion.kiev.ua 10.0-CURRENT FreeBSD 10.0-CURRENT #0 r254417M: 
Fri Aug 16 21:53:47 EEST 2013 
root at scorpion.kiev.ua:/usr/obj/usr/src/sys/Kernel  amd64

After first attach USB Flash drive - is good mount. After detach and 
attach again, USB Flash drive not detected any more.
If enter "shutdown -r now" system not  be rebooting.

The flash drive silicon-Power16G PMAP does not work at all.

In build FreeBSD at Jul 28  2013  it's work fine.