2.5.45 (vanilla ? mcp1) build error

on both version ( linux-2.5.45 and linux-2.5.45-mcp1):
i have this problem:
gcc -Wp,-MD,net/ipv4/.ipmr.o.d -D__KERNEL__ -Iinclude -Wall

(quoted diff) +0 -4

-Wstrict-prototypes -Wno-trigraphs -O2 -fomit-frame-pointer 
-fno-strict-aliasing -fno-common -pipe -mpreferred-stack-boundary=2 
-march=i686 -Iarch/i386/mach-generic -nostdinc -iwithprefix include    
-DKBUILD_BASENAME=ipmr   -c -o net/ipv4/ipmr.o net/ipv4/ipmr.c

net/ipv4/ipmr.c: In function `ipmr_forward_finish':
net/ipv4/ipmr.c:1114: structure has no member named `pmtu'

net/ipv4/ipmr.c: In function `ipmr_queue_xmit':
net/ipv4/ipmr.c:1170: structure has no member named `pmtu' net/ipv4/ipmr.c: At top level:
net/ipv4/ipmr.c:111: warning: `pim_protocol' defined but not used make[2]: *** [net/ipv4/ipmr.o] Error 1
make[1]: *** [net/ipv4] Error 2
make: *** [net] Error 2
error: Bad exit status from /var/tmp/rpm-tmp.3879 (%build)