It has postgresql as dependency, but (IMHO) libpq should be enough. This ends up in installing the whole postgresql suite instead of just the client library. Not quite optimal ;-P Seems, in 7.x times there was only one big monolithic postgesql port and the splittof was done later, which has not been reflected in dependencies. (BTW: It seems many packages have this problem ...)
*** This bug has been marked as a duplicate of 158950 ***
Dupe.