Panic with 9.0 Beta 1 (arcmsr.c)

Hi,

i tried to install FBSD 9.0 beta 1. Booting the install-cd stopped with a
kernel panic:

panic: _mtx_lock_sleep: recursed on non-recursive mutex arcmsr Q buffer lock
_at_ /usr/src/sys/dev/arcmsr/arcmsr.c:2093

A screenshot from the panic can be found here:
http://ugrohnwaldt.web02.lando.us/FBSD/arcmsr.png

Chers,
Uwe