  We present Very Large Array (VLA) observations of H2O and OH masers, as well
as radio continuum emission at 1.3 and 18 cm toward three sources previously
cataloged as planetary nebulae (PNe) and in which single-dish detections of H2O
masers have been reported: IRAS 17443-2949, IRAS 17580-3111, and IRAS
18061-2505. Our goal was to unambiguously confirm their nature as
water-maser-emitting PNe, a class of objects of which only two bona-fide
members were previously known. We detected and mapped H2O maser emission toward
all three sources, while OH maser emission is detected in IRAS 17443-2949 and
IRAS 17580-3111 as well as in other two objects within the observed fields:
IRAS 17442-2942 (unknown nature) and IRAS 17579-3121 (also cataloged as a
possible PN). We found radio continuum emission associated only with IRAS
18061-2505. Our results confirm IRAS 18061-2505 as the third known case of a PN
associated with H2O maser emission. The three known water-maser-emitting PNe
have clear bipolar morphologies, which suggests that water maser emission in
these objects is related to non-spherical mass-loss episodes. We speculate that
these bipolar PNe would have ``water-fountain'' Asymptotic Giant Branch (AGB)
and post-AGB stars as their precursors. A note of caution is given for other
objects that have been classified as OHPNe (objects with both OH maser and
radio continuum emission, that could be extremely young PNe) based on
single-dish observations, since interferometric data of both OH masers and
continuum are necessary for a proper identification as members of this class.
