The Patriots have signed DT Gerard Warren.  The 31-year old played in all 16 games for the Raiders last season and he had 35 tackles, 2 sacks, he had 3 tackles for a loss and he defensed 1 pass.  Warren has now played in 135 games in his NFL career and he has made 295 tackles, he has defensed 13 passes, has 32 sacks and he has forced 7 fumbles.  Warren will probably backup Vince Wilfork in 2010 giving him a breather once in a while.