FreeBSD 5.3-STABLE: PHP 5.0.2 won't compile

[O. Hartmann]

Hello.
Under FreeBSD 5.3-STABLE, PHP 5.0.2 from ports collection will not 
compile anymore. Compilation ends up with
ext/standard/dns.lo(.text+0x1d49): In function `.L166':
: undefined reference to `res_ninit'
ext/standard/dns.lo(.text+0x1db5): In function `.L166':
: undefined reference to `res_nmkquery'
ext/standard/dns.lo(.text+0x1de7): In function `.L166':
: undefined reference to `res_nsend'
ext/standard/dns.lo(.text+0x1f6a): In function `.L166':
: undefined reference to `res_nclose'
*** Error code 1

I found some threads about BIND/BIND9 relating things and it seemed to 
me that BIND9 is neccessary to compile PHP 5.0.2 properly but I thought 
BIND9 is now standard in 5.3.
In /etc/make.conf with "WITH_BIND_LIBS= true" enabled, I built world 
again hoping I get a possibly missing library or .h file to get php 
compiling as expected, but with no success. Is there a hint to come 
along with this?

Thanks a lot
Oliver