  In a recent NMR investigation of the iron-based superconductor
(La0.87Ca0.13)FePO [Phys. Rev. Lett. 101, 077006 (2008)] Y. Nakai et al.
reported an anomalous behavior of the nuclear spin-lattice relaxation of 31P
nuclei in the superconducting state: The relaxation rate 1/T1 strongly depends
on the measurement frequency and its T dependence does not show the typical
decrease expected for the superconducting state. In this short note, we point
out that these two observations bear similarity with the situation is some of
the high Tc cuprates.
