Translation messages

Hi,

I want to tranfer the messages in logon language.

I am tranfering the all the messages in to internal table then finally I am writing into spool.

For Example If 'Document not found in SAP', these type text I am putting into internal table.

Now I want to write the internal table messages into Spool based on logon language. How can I do this.

Thanks & Regards

Venkat