I think linksys PoE device to procurve PoE switch have fristly autonegotiation issue
not to be complated autonegotiation between both device
in conclusion we can see some issue (PoE issue,packed drop issue etc.)
we solve fristly autonegotiation both device
example test
connect linksys device on procurve PoE device
with utp straight true patch cable for example int 17
set up int 17 mdix mode and speed-duplex settings
(eth-17)# mdix-mode mdix
(eth-17)# speed-duplex 100-full
and make linksys device ethernet port setup 100 full
test now PoE operation