"fpudna in kernel mode!" running qemu on amd64

[Markus Trippelsdorf]

Whenever I run a XP guest system on my amd64 host in qemu the
system message buffer is being filled with the following warning:
"fpudna in kernel mode!"
This message is repeated ad nauseam. (It seems to be harmless, however.)
As a first aid I simply commented out the printf in
src/sys/amd64/amd64/trap.c, but I'm wondering if there is a deeper
underlying problem. 
-- 
Markus