Subledger Validation against custom UDC?

I've read in World documentation that there is functionality to create a new subledger type, and cause it to be  validated against a UDC table by adding "U 55/01" to the description 2 field in the Subledger Type UDC, where 55/01 is a custom UDC table.  When reviewing the same documentation for E1, I do not see this functionality described.

Can you create a new subledger type that is validated against a UDC table?  If so, how is this functionality activated?  So far in my tests, this had now worked in E1.

Thanks.