[SQL] How to rename a constraint/trigger??

[Andrei Bintintan]

Hi to all,   I have a database, where in the tables I have around 100 constrains (link to other tables) that don't have a name "<unnamed>" or they have a name like "$1" "$2". Now, I have a module which bases on the same structure, but I get some query errors from a "<unnamed>" constraint. I really don't know exaclty  which the constrain generates the error, in that table I have 12 such constrains.   Does anyone have a script or it exist a command so that I can rename all the "<unnamed>"constrains in this database?   I'm using postgre 7.3.2.   Thankx, Andy.