close inactive client connection

Hello,  

 I am developing a system, using the ZeosLib, which maintains a
permanent connection to the database.  

 When the client loses the connection, the server does not recognize
this and keeps the connection as if it were active. When the client
attempts to reconnect, the server creates a new connection and the
previous remains active.

 This has caused an excessive increase in the number of active
connections and hampered the use of the system.  

 Have any way or setting to make postgres close idle connections?
--  
Luiz Agnaldo Bernardi
Fone 41 36755756
     41 99979849