Getting panic on uhci.c: uhci_abort_xfer()

[R.Mahmatkhanov]

Good day!

A couple of weeks ago i begun meeting with system hangs and arbitrary 
reboots. It occurs when some intensive traffic come into play with using 
mobile usb modem. After i move to todays RELENG_7 (from ex-7 -CURRENT) i 
saw this message after arbitrary reboot in /var/log/messages:

Oct 13 23:54:04 nx7400 syslogd: kernel boot file is /boot/kernel/kernel
Oct 13 23:54:04 nx7400 kernel: panic: uhci_abort_xfer: not in process 
context
Oct 13 23:54:04 nx7400 kernel: cpuid = 0
Oct 13 23:54:04 nx7400 kernel: Uptime: 2h53m44s
Oct 13 23:54:04 nx7400 kernel: Physical memory: 747 MB
Oct 13 23:54:04 nx7400 kernel: Dumping 147 MB: 132 116 100 84 68 52 36 20 4
Oct 13 23:54:04 nx7400 kernel: Dump complete
Oct 13 23:54:04 nx7400 kernel: Automatic reboot in 15 seconds - press a 
key on the console to abort
Oct 13 23:54:04 nx7400 kernel: --> Press a key on the console to reboot,
Oct 13 23:54:04 nx7400 kernel: --> or switch off the system now.
Oct 13 23:54:04 nx7400 kernel: Rebooting...

This panic is initiated if (xfer->device->bus->intr_context || !curproc) 
in uhci_abort_xfer(). What i can do to eliminate such situations or what 
i do wrong?

My system is FreeBSD 7.0-PRERELEASE i386 GENERIC from todays cvs.

Thanks in advance for answer.