There's no way to get historical deadlocks in SQL 2005 unless you already had some traceflag or trace on at the time.
To catch future deadlocks, turn traceflag 1222 on, the deadlock graph will then be written to the error log.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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