Sidhu,
Yes you can post a message via a HTTP Send Port from one BizTalk environment to a second BizTalk environment that is listening via a HTTP Receive Location. If you’re doing more than simply invoking a web-page – i.e. you’re sending a message that needs to be actioned in some way – you may want to consider using a web-service and the SOAP adapter for this task.
Regards, Nick.