If you want to supplement a language after EHP Upgrade process then you can do this easily via transaction SMLT with the following steps..

Go to transaction SMLT

Select the language which you want to supplement

Go to ;

Language –> Special Actions –> Supplementation (Basic)

Fill the “Description” area , select tables for supplementation and EXECUTE

Click the YES button for the following screen

Now you can see your process as a line under the related language with Truck symbol.

Finally its completed as shown below.