Need help in using search_replace function against persistent cache datastore

Hi ,

I am trying to do search_replace in one of my transformation and i am getting the below error:

A NULL replace value is specified in the function <search_replace>. NULL replace value is not allowed for Word and Substring

Sample values from my table are :

SRCH_VAL             REPLACE_VAL   

-------------------                 --------------

@NOEMAIL.                  NULL        

@NO_EMAIL.                NULL 

@NO-EMAIL.                 NULL       

i NEED TO replace with null for some of the banned key words in email address.

i was trying to do with Search_replace and it is throwing above error.

Please blow some light to fix these error

i tried to give physical table from DB2 and it is also giving the same error.

Thanks,

Sreenivas