CTBW - Classification data with time dependency

I have created a DataSource for Equipment master classification attributes using transaction CTBW. The generated Extract Structure contains fields DATEFROM and DATETO but they are SAP hidden.

Is there a way to get time dependent values for a classification characteristic? We are on R/3 version 4.6C and BW30B . The extractor works fine for extracting the current value in effect for the characteristic, but the users need historical values also. Change pointer tracking is active for the characteristic in R/3.

Thanks

Vineet