Bought a spare 3111 handset and cant connect it to my base. it looks as if it was connected to another base at one time. screen just says "connecting..." and there is nothing I can do to clear it. Can the phone be reset so I can connect it to my base?

Usually. Model number means everything. Assume you can, you need to register the handset to the base. This is in a manual and is not the same for all panasonic models. Look up the model of the handset and the base. You cannot buy any panasonic handset and have it work. You must match them. Last time, I bought a new set.

they should be, but you may not be able to reprogram the handset that came with the base, to another base.
It seems that the ones sold with the base are slaves to that base.
The company does make a replacement handset available that can be programed to any base.

www.telephones.att.com or call
1 (800) 222-3111.

Remove then replace the batteries from the hand set. You should now get dial tojo.

sounds as its still damp inside of handset. u could strip down and make sure the water hasnt coroided any contacts which is making it discharge to earth.
with regurds replacement handsets , i have been looking for spare base as mine is just started going and cuts calls off ( sound like dry joint in base unit or power supply is giving up) try a philps dealer to see what spares philps have other than that it secound hand units.

This fixed mine:

1/15/10

To fix this issue:

1. Unplug the Unit
2. Unplug the Phone Cord
3. Disconnect the Battery from the Handset
4. Wait 10-15 minutes… and put back together in Reverse Order
5. Connect the Handset Battery
6. Plug-in the Phone Cord
7. Plug-in the Unit

If the other three handsets work ok then you have a defective handset.

it may be that the handset is registred to another base unit-
we had one base and one handset replaced by uniden, but the second (old) handset was still registred to the old base, therefore everytime we tried to deregister the handset it was looking for the old (replaced) base and of course could not connect and therefore wouldnt deregister. still havent figured out what to do yet

You need to register the new handset with the base.
In Global settings De-register the new handset then place it on the main base unit connected. It should then register.

Unplug the battery. Hold down The * (star) and the #(hash) keys simultaneously. Re-connect the battery, phone will beep and screen will be blank. Press the voicemail (righthand silver key under the lcd screen). As above EEPROM/RAM message will appear. Place handset on base and your problem is solved.

Check that you have the larger power adaptor connected to the base unit.