Not sure what version of DB Server you're running, but from the release notes:
Release Number 7.5.000.10 [11/16/07] – Hot Fix
Corrections and Modifications
This release includes the following correction and modification:
For MS SQL Server database engines, DB Server now correctly handles named parameters when calling stored procedures. Therefore, a procedure can be called with its parameters in any order, and parameters using default values can be omitted.
Previously, when a stored procedure was called with the order of the parameters different from the order specified during stored procedure creation, or with some parameters using default values omitted, the execution of the procedure would produce either an incorrect result or fail completely.
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Also:
Release Number 7.6.000.08 [02/14/08] – General
Corrections and Modifications
This release includes the following corrections and modifications that were made between the initial release of 7.6 and this 7.6 release:
For MS SQL Server database engines, DB Server now correctly handles named parameters when calling stored procedures. Therefore, a procedure can be called with its parameters in any order, and parameters using default values can be omitted.
Previously, when a stored procedure was called with the order of the parameters different from the order specified during stored procedure creation, or with some parameters using default values omitted, the execution of the procedure would produce either an incorrect result or fail completely.
(ER# 173530495)
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