IBM Key Management Utility (IKEYMAN)

Procedure to add/merge the Intermediate certificate from Verisign to Key Database

-- First Install IBM HTTP Server on your local machine. This will also install the Key Management Utility

http://www-01.ibm.com/software/webservers/httpservers

-- Obtain the updated VeriSign Intermediate CA by going to the Intermediate CA Certificate page. 

http://www.verisign.com/support/verisign-intermediate-ca/secure-site-intermediate/index.html

 select and save the appropriate certificate in a text file  .txt

-- Start the IKEYMAN user interface. (On Windows operating systems: Click Start > Programs > IBM HTTP Server > Start Key Management Utility.)

-- Click Key Database File from the main user interface, and then click Open.

--  In the Open dialog box, enter your key database name or use the Browse option Click OK. (Select type "CMS".)

-- In the Password Prompt dialog box, enter your correct password

-- Under Key database content, click Signer Certificates and then click Add.

-- In the Add CA’s Certificate from a File dialog box, enter the filename or location to the .txt file, or use the Browse option. Click OK.

In the Enter a Label dialog box, enter a label name such as “VeriSign Intermediate CA” and click OK.

Newly added as “VeriSign Intermediate CA” is shown as below

For more information how to use the Key Management Utility (IKEYMAN)
http://www-306.ibm.com/software/webservers/httpservers/doc/v1319/9atikeyu.htm

 Very very useful link about SSL
https://knowledge.verisign.com/support/ssl-certificates-support/index?page=content&id=AR796

Once you have generated the CSR, you will be able to confirm if it is ok for use by accessing the below link:
https://knowledge.verisign.com/support/ssl-certificates-support/index?page=content&id=AR1474