You can, all you have to do is distinguish the data-target attribute with a unique class or identifier for the dropdown menus, for example:
For your first drop down menu
 <a class="btn btn-navbar" data-toggle="collapse" data-target="#first"> 
For your second dropdown:
 <a class="btn btn-navbar" data-toggle="collapse" data-target="#second"> 
Then you can add this unique identifier to the container with the crash navigation:
First
 <div id="first" class="nav-collapse"> ... </div> 
Second
 <div id="second" class="nav-collapse"> ... </div> 
Demo: http://jsfiddle.net/F2tYu/3/