XA support was tested against the following Microsoft SQL Server versions:
Before using the Microsoft SQL Server XA features, you must install and register the Microsoft SQL Server extended stored procedures, for this :
1) copy xp_oplxa.dll ( xp_oplxa65.dll for MSSQL 6.5) to the MSSQLServer_Root/binn directory
2) execute the command :
isql.exe -Usa -Psa_pwd -ig:xp_oplxa.sql
or
isql.exe -Usa -Psa_pwd -ig:xp_oplxa65.sql (for MSSQL 6.5)