I installed the sources from 1.5, then patched them with the
appropriate diffs on a 1.5.2 host.

I got exactly two problems :-(

1. /usr/src/crypto/dist/heimdal/lib/asn1/k5.asn1 has duplicate entries
in that

-- message types
        
krb-as-req INTEGER ::= 10 -- Request for initial authentication
krb-as-rep INTEGER ::= 11 -- Response to KRB_AS_REQ request
krb-tgs-req INTEGER ::= 12 -- Request for authentication based on TGT
krb-tgs-rep INTEGER ::= 13 -- Response to KRB_TGS_REQ request
krb-ap-req INTEGER ::= 14 -- application request to server
krb-ap-rep INTEGER ::= 15 -- Response to KRB_AP_REQ_MUTUAL
krb-safe INTEGER ::= 20 -- Safe (checksummed) application message
krb-priv INTEGER ::= 21 -- Private (encrypted) application message
krb-cred INTEGER ::= 22 -- Private (encrypted) message to forward credentials
krb-error INTEGER ::= 30 -- Error response

duplicate the earlier 

-- message types

MESSAGE-TYPE ::= INTEGER {
        krb-as-req(10), -- Request for initial authentication
        krb-as-rep(11), -- Response to KRB_AS_REQ request
        krb-tgs-req(12), -- Request for authentication based on TGT
        krb-tgs-rep(13), -- Response to KRB_TGS_REQ request
        krb-ap-req(14), -- application request to server
        krb-ap-rep(15), -- Response to KRB_AP_REQ_MUTUAL
        krb-safe(20), -- Safe (checksummed) application message
        krb-priv(21), -- Private (encrypted) application message
        krb-cred(22), -- Private (encrypted) message to forward credentials
        krb-error(30) -- Error response
}       

2. I can't seem to get DHCP to compile, there's some inconsistency
that results in:

cc   -o dhcpd dhcpd.o dhcp.o bootp.o confpars.o db.o class.o failover.o omapi.o mdb.o stables.o salloc.o ddns.o /usr/src/usr.sbin/dhcp/common/libdhcp.a /usr/src/usr.sbin/dhcp/minires/libminires.a /usr/src/usr.sbin/dhcp/omapip/libomapi.a /usr/src/usr.sbin/dhcp/dst/libdst.a
/usr/lib/crt0.o: In function `___start': 
/usr/lib/crt0.o(.text+0xc1): undefined reference to `main' 
ddns.o: In function `ddns_update_ptr':
ddns.o(.text+0x57): undefined reference to `minires_mkupdrec'
ddns.o(.text+0xaa): undefined reference to `minires_mkupdrec'
ddns.o(.text+0xfa): undefined reference to `resolver_state'
ddns.o(.text+0xff): undefined reference to `minires_nupdate'
ddns.o(.text+0x10b): undefined reference to `print_dns_status'
ddns.o(.text+0x155): undefined reference to `minires_freeupdrec'
ddns.o: In function `ddns_remove_ptr':
ddns.o(.text+0x19a): undefined reference to `minires_mkupdrec'
ddns.o(.text+0x1ea): undefined reference to `resolver_state'
ddns.o(.text+0x1ef): undefined reference to `minires_nupdate'
ddns.o(.text+0x1fb): undefined reference to `print_dns_status'
ddns.o(.text+0x245): undefined reference to `minires_freeupdrec'
ddns.o: In function `ddns_updates':
ddns.o(.text+0x36a): undefined reference to `server_universe'
ddns.o(.text+0x36f): undefined reference to `lookup_option'
ddns.o(.text+0x3a6): undefined reference to `evaluate_boolean_option_cache'

... and then some.  This I could not track down.  The fact that the
sources are scattered in /usr/src/dist/dhcp made it more difficult.
But if someone else has seen this and fixed it, I have a fast host to
compile on, I'm only too happy to try again.

++L