Oracle tier 2 unable to recognize HTTP/HTML functions in multiprotocol mode


I am recording an application that uses Oracle tier 2 protocol. However, there is a single step where I need to pass customized 'web_custom_request'. Since web_custom_request is web based functions, I recorded flow in multi-protocol mode (Oracle tier 2 and HTTP/HTML). While replaying the script, I am getting below error:

Error: C interpreter run time error: Action.c (10110): Error -- Unresolved symbol : web_custom_request.

I also checked passing only this function through web http/html protocol and it worked while in multi-protocol , its not working. Seems like Oracle toer 2 is unable to use HTTP library, Is there any configuration which needs to be set up for this? Please suggest...