How to add 6000 character for metadata in WCC

Hi

We have a requirement to have one field where user can add data near to 6000 character.

For this we have created one metadata i.e Comments as a memo. It created varchar2 data type after db design updated from configuration. In oracle Varchar2 has the limitation to store maximum of 4000 characters. I even tried with changing the data type of column at database from Varchar2 to CLOB. But while passing the data I am getting below error.

Content item 'D_1516178' was not successfully checked in. The value entered for 'Comments' exceeds 2,000 characters, the maximum length allowed for this field.