You posted the this question in SQL Server 2000 forum, are you running that version?
Trace flag 2371 did not exist until SQL Server 2008.
Either way came across a few articles that deal directly with AX:
SQL Server Trace Flags for Dynamics AX
SQL Server Trace Flag 2371 for Dynamics AX
Shawn Melton
Twitter: @wsmelton
Blog: wsmelton.github.com
Github: wsmelton