Submenus (dropdowns) truncated and not displayed on mobile devices - html

Question

I'm developing a web with Ruby on Rails, using Twitter-Bootstrap and Simple-Navigation gem. The navigation menu works fine on any browser, something like this:
When displaying the web on a mobile device and clicking the nav button, the whole menu is displayed on vertical block, enlarging the size of the header to a max. height than can hold the menu. The problem is that opening any submenú increases the size of the menu, overflowing and hiding the last options, as you can see in the comparison:
Any idea?
The code of nav_menu on the mobile version:
<div class="navbar navbar-static-top">
<div class="navbar-inner">
<div class="container">
<a class="btn btn-navbar" data-target=".nav-collapse" data-toggle="collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
<div class="brand">
<img alt="NRG Consulting logo" src="/assets/nrg-logo.png" title="NRG Consulting">
</div>
<span class="development" id="rails-env"><span>development</span></span>
<div class="container nav-collapse in collapse" style="height: 496px;">
<ul class="nav pull-right align-top">
<li>
<a href="manual_path">
Help
</a>
</li>
<li>
Español <img alt="Switch to English" class="lang" data-locale="en" src="/assets/lang-es.png" title="English">
</li>
</ul>
<ul class="nav pull-right align-bottom">
<li id="home">Home</li>
<li id="formulas">Formulas</li>
<li id="deals">Deals</li>
.
.
.
<li class="active dropdown" id="admin">
Admin <b class="caret"></b>
<ul class="dropdown-menu">
<li id="subscription">Subscriptions</li>
<li class="divider" id="nav_header"></li>
<li id="historic">Recalculate historic prices</li>
<li class="divider" id="nav_header"></li>
<li id="export">export data</li>
<li id="import_tuple_eod_check">Check data</li>
<li class="divider" id="nav_header"></li>
<li id="alerts">Alert</li>
<li id="product_price_alerts">Price alerts</li>
<li id="import_tuples">Import tuple</li>
<li id="fixing_errors">fixing errors</li>
<li class="divider" id="nav_header"></li><li id="redis">Resque</li>
<li id="copycopter">Translate</li>
<li class="divider" id="nav_header"></li>
<li class="active simple-navigation-active-leaf" id="client">Clients</li>
<li id="user">Users</li>
<li id="user_activities">User activity</li></ul></li>
<li id="user">Users</li>
</ul>
</div>
</div>
</div>
</div>

Answer 1

Collapsed nav menu appears to set a fixed height value when displaying nav menu, preventing the div to enlarging when submenu dropdowns display:
<div class="container nav-collapse in collapse" style="height: 496px;">
Adding this lines to style.css set height property to auto, allowing the div to enlarge when needed, showing the whole menu:
.container.nav-collapse.in.collapse{
height: auto !important;
}
Perhaps there is a cleaner solution, but this worked pretty fine for me, and don't want to change Bootstrap code itself.
A link displaying some usefull info about similar issues.