Postgres 6.5.1 on Solaris 2.6

I am having some problems compiling Postgresql on Solaris 2.6. I get an
error when I do "make all" and I get to the libpq compilation. This is
the message I get:

make -C libpq++ all
make[2]: Entering directory
`/usr/share/src/pgsql/postgresql-6.5.1/src/interfaces/libpq++'
g++ -Wno-error -I../../backend -I../../include -I../../interfaces/libpq
-I../../include -I../../backend    -Wall -Wmissing-prototypes -fPIC   -c
pgconnection.cc -o pgconnection.o
In file included from pgconnection.cc:20:
pgconnection.h:24: string: No such file or directory
make[2]: *** [pgconnection.o] Error 1
make[2]: Leaving directory
`/usr/share/src/pgsql/postgresql-6.5.1/src/interfaces/libpq++'
make[1]: *** [all] Error 2
make[1]: Leaving directory
`/usr/share/src/pgsql/postgresql-6.5.1/src/interfaces'
make: *** [all] Error 2

I suppose I can compile it without the libpq option but, if I don't,
what can I do?
Thank you,

            Esteban Chiner

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 Esteban Chiner Sanz        mailto (work): echiner@tissat.es
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