problems compiling 5-stable

[Mipam]

Hi,

I am trying to compile the source of RELENG_5 on a 5.2.1 system.
It doesnt get far:

cc -O -pipe  -DLIBC_SCCS -I/usr/src/lib/libkvm  -c 
/usr/src/lib/libkvm/kvm_getswapinfo.c
cc -O -pipe  -DLIBC_SCCS -I/usr/src/lib/libkvm  -c 
/usr/src/lib/libkvm/kvm_proc.c
/usr/src/lib/libkvm/kvm_proc.c: In function `kvm_proclist':
/usr/src/lib/libkvm/kvm_proc.c:269: warning: assignment makes integer from 
pointer without a cast
/usr/src/lib/libkvm/kvm_proc.c:341: error: structure has no member named 
`p_runtime'
*** Error code 1

Stop in /usr/src/lib/libkvm.
*** Error code 1

Stop in /usr/src.
*** Error code 1

Any hints what i could do to remedy this or another way to upgrade?
Bye,

Mipam.