In a message dated 9/27/05 6:04:13 AM, RAlanen@AOL.COM writes:

<< Kevin, most likely the pigtail sockets have gotten overheated from poor 
contact. >>

Quite the opposite.… 

Kevin, most likely the pigtail sockets have gotten overheated from EXCESSIVE 
CURRENT .  A marginal connection (poor contact) would result in a voltage drop 
across the connection.  The worse the connection is (i.e., the higher the 
contact resistance), the LESS the current conducted through the circuit.  Since 
the lamps are in series with this connection, the lamps will dim even to the 
point of appearing to be unlit.  A poor connection is a nuisance, but it will 
reduce the current in the circuit preventing any meltdown.

If the insulation of the conductors or the plastic of the components in your 
lighting system is melting, reduce the load on the system or install a system 
which is rated to swing the existing load.

George