memory overflow

Hi all!
I'm trying to run l4 on qemu. I've successfully build the kernel and the
user level code. I have followed the guide from l4ka :
http://l4ka.org/projects/pistachio/ia32/gettingstarted.php
and everything is running well except some little thing but i think it
doesn't matter (like problem when unmounting,...).
but whem i run qemu with qemu -fda fdimage.img, i got this message :
Memory descriptor overflow (max=200, n=200)
--- "KD# memdesc overflow" ---
------------------------------ ---------------9eip=f0102358, esp=f010ee400
---

then everything is locked>
Do you know how i can solve that?
Thanks.
Antoine