Free agent safety Michael Boulware signed with the Vikings, giving them some depth in the defensive backfield and on special teams. Boulware was a backup safety last season for the Houston Texans, made six special team tackles and blocked an extra-point attempt The Vikings also signed defensive lineman Kendrick Allen, who missed all of 2007 because of lingering effects from a foot injury. He played two games for the Packers in 2006.