strange msg...

[Marek Blaszkowski <mb_(_at_)_kis_(_dot_)_p_(_dot_)_lodz_(_dot_)_pl>]

Hi.
I just found in my /var/log/messages :

Aug 30 22:10:11 gate /bsd: Data modified on freelist: word 0 of object 0xf099e780 size 128 previous type ??? (invalid addr 0x8d33)
Aug 30 22:10:11 gate /bsd: Data modified on freelist: word 0 of object 0xf099e780 size 128 previous type ??? (0x0 != 0xdeadbeef)
Aug 30 22:16:03 gate /bsd: Data modified on freelist: word 0 of object 0xf09c1000 size 40 previous type ??? (invalid addr 0xdb33)
Aug 30 22:16:03 gate /bsd: Data modified on freelist: word 0 of object 0xf09c1000 size 40 previous type ??? (0x0 != 0xdeadbeef)

my system is x86 -current...
What kind of mesg is that kernel  warning  ?
That mesg is always when I use pppd (I guess) ...

regards,
Marek B.