How to add controls from other project

Hi,
I have a solution with 2 web projects. In the first project I have some controls that I want to use in my second project.
I have added an referrence to the first project and added the following code to the web.config:
<add tagPrefix="CMS" assembly="Pangaea.CMS.Module.Controls" namespace="Pangaea.CMS.Module.Controls"/>
In the aspx file (project 2) Visual Studio reconize the controls in the assemby Pangaea.CMS.Module.Controls, but when its trying to render the controls, the codebehind of the controls does not reconize the textboxes and buttons that are defient in the aspx of the control.
When I render the controls in project 1, they work just fine.

Does someone have a sollution for this problem?
Thx.

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