Cisco Firewall :: Setting Up Port Forwarding ASA 5505

We are trying to setup our ASA 5505 to do port forwarding to multiple internal servers and have run into some issues. A little background on what we are trying to do.
 
We have 1 static external IP. Internally we have one exsisting server (10.1.1.184) that has port 80 forwarded to it and another exsisting server (10.1.1.185) that has port 443 forwarded to it. Both of these servers are serving seperate web apps to our employees who of course use them offsite. We have now added an additional server (10.1.1.186) that needs to use both ports 80 and 443. Is there any way to set it up so that these ports can be forwarded to all the servers that need them? Also, how would this work as far knowing what traffic will need to go to which server even though it is using the same port?
 
The equipment is: ASA 5505ASA Version 7.2(4)ASDM Version 5.2(4)   I appologize in advance if what I'm trying to do is difficult/impossible. I inherted the ASA 5505 at this location and I was not here when it was initially installed. In fact no one on staff was here when it was initially installed. I did manage to find the passwords to it though. I'm not at all familiar with the ASA 5505 or Cisco secuirty appliances in general.