Upgrading 5.2 and Kerberos5 error

	Upgrading 5.1Rel -> 5.2Rel
'MAKE BUILDWORLD' ends with the following error:

===> lib/libtelnet
rm -f .depend
mkdep -f .depend -a    -I/usr/src/lib/libtelnet/../../contrib/telnet 
-DENCRYPTION -DAUTHENTICATION -DSRA -DKRB5 -I/lib/krb5 -I -I -DFORWARD -Dnet
...
cc1: /lib/krb5: Not a directory
...
mkdep: compile failed
*** Error code 1

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

PS.	Yesterday I 'MAKE -j4 BUIDWORLD' 'MAKE BUIDKERNEL' 'MAKE INSTALLKERNEL' 
from 5.2Rel source without a glitch but 'MAKE INSTALLWORLD' crashed with some 
lib/libexec error and unbootable system. I've reinstalled minimal 5.0Rel from 
CD and successfully rebuild 5.1Rel from source.

Thanks in advance 
Dmitri