Execute Stored Procedure: Invalid Column Type

I have a stored procedure in Oracle DB which takes in five number (integer) input parameters as i/ps and returns a Ref_Cursor p_results and a varchar - p_output_msg as the o/p.
When tried to execute this process using the Execute Stored Proc node with same named parameters and same data-type, it throws out an error: 

There is a problem with task “Execute Stored Procedure” in the process “test_storedproc”. java.sql.SQLException: Invalid column type: 10505

Can someone let me know if the o/ps are supposed to be defined when using the function in an expression rule: executestoredprocedure()?

Any help regarding this issue will be helpful. Thanks in advance!