Missing Syntax

I have noticed that in the openldap system I am using, the schema has a missing syntax. This syntax is "1.3.6.1.4.1.1466.115.121.1.58" ; "Substring Assertion". This is referenced in matching types using partial matching of strings (exactsubstringsmatch, numericStringSubstringsMatch, ...). I am fairly new to these subjects and do not understand fully how they operate.

Is there a way to correct this? Are the syntaxes and matching types specified in a way that can be modified dynamically?

-Nikkos