(Renton, WA)  --  The Seattle Seahawks have another free-agent offensive lineman on their roster.  The team says J'Marcus Webb, who played last season for Oakland, has been signed to a two-year deal worth six-point-25-million dollars.  SeattlePI.com reports Webb started 16 games at guard for the Raiders last year, but the Seahawks have him listed as a tackle.  The new contract makes him the highest-paid offensive lineman currently on Seattle's roster.