Deployed aspx page can't access methods from same project
<p>I'm using ASP.NET with VB, and .NET version 3.5.  In the project, I've got some utility functions that I call from expressions in the aspx pages and also in code behind.  This all works fine on my local machine, but when I deploy to the production server, I get this compilation error on each of those utility methods:</p>

<pre><code>BC30456: 'XXX' is not a member of 'String'.
</code></pre>

<p>where XXX is an extension method defined on System.String.  I'm baffled about this for a number of reasons:</p>

<ol>
<li>Why is ASP.NET compiling anything at all, since I've precompiled the application and put everything in the bin directory.</li>
<li>ASP.NET knows the functions are there because they work in code behind.  It's only when used in the aspx page that I have this problem.  (e.g. if I do something like this: &lt;%= "A string to XXX-ify".XXX())%>)</li>
<li>This method <strong>is</strong> public, which I verified with Reflector.</li>
<li>I imported the relevant namespaces in the web.config file, and I can see that these namespaces are being imported in the call that ASP.NET makes to the compiler.</li>
</ol>

<p>What on earth is going on here?  I really need access to these utility functions because, well, they're really useful.</p>
