Yes. You didn't export anything for the library so the linker didn't need to create a lib.
You have to add Q_DECL_EXPORT to every class you want to export.
Something like:
Qt Code: 
  1. //==========================================================//
  2. //                                                          //
  3. //   Diplomprojekt Calina (platformuebergreifende 3d GUI)   //
  4. //                                                          //
  5. //==========================================================//
  6. // Autoren: Adam Celarek (diplom_arbeit at xibo at)         //
  7. //           Patrick Freninger ()                           //
  8. //           Sebastian Raggl ()                             //
  9. //==========================================================//
  10.  
  11. /***************************************************************************
  12.  *   This program is free software; you can redistribute it and/or modify  *
  13.  *   it under the terms of the GNU General Public License as published by  *
  14.  *   the Free Software Foundation; either version 2 of the License, or     *
  15.  *   (at your option) any later version.                                   *
  16.  *                                                                         *
  17.  *   This program is distributed in the hope that it will be useful,       *
  18.  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  19.  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  20.  *   GNU General Public License for more details.                          *
  21.  *                                                                         *
  22.  *   You should have received a copy of the GNU General Public License     *
  23.  *   along with this program; if not, write to the                         *
  24.  *   Free Software Foundation, Inc.,                                       *
  25.  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  26.  ***************************************************************************/
  27. #ifndef CALINAGLWIDGET_H
  28. #define CALINAGLWIDGET_H
  29.  
  30. #include <QGLWidget>
  31. #include "helper.h"
  32.  
  33. namespace calina {
  34.  
  35. /**
  36.  * @brief
  37.  *
  38.  *
  39.  *
  40.  * @author Adam Celarek <testman@xibo.at>
  41.  * @todo Dokumentation von da Klassn.. Wegn Prototyp deadline keine Zeit..
  42.  */
  43.  
  44. class World;
  45.  
  46. class [B]Q_DECL_EXPORT[/B] GLWidget : public QGLWidget {
  47.     Q_OBJECT
  48. public:
  49.     GLWidget(WidgetList& widgetList, QObject *parent = 0);
  50.     ~GLWidget();
  51.  
  52.     void initializeGL();
  53.     void resizeGL(int w, int h);
  54.     void paintGL();
  55.     World* parentWorld() const;
  56.  
  57. private:
  58.     WidgetList& p_widgetList;
  59. };
  60.  
  61. }
  62.  
  63. #endif
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I added them and got:
Generating Code...
cl -c -nologo -Zm300 -Zi -MDd -GR -EHsc -W3 -w34100 -w34189 -DUNICODE -D
WIN32 -DQT_LARGEFILE_SUPPORT -DQT_DLL -DQT_XML_LIB -DQT_OPENGL_LIB -DQT_GUI_LIB
-DQT_CORE_LIB -DQT_THREAD_SUPPORT -I"c:\Qt\4.3.0rc1\include\QtCore" -I"c:\Qt\4.3
.0rc1\include\QtCore" -I"c:\Qt\4.3.0rc1\include\QtGui" -I"c:\Qt\4.3.0rc1\include
\QtGui" -I"c:\Qt\4.3.0rc1\include\QtOpenGL" -I"c:\Qt\4.3.0rc1\include\QtOpenGL"
-I"c:\Qt\4.3.0rc1\include\QtXml" -I"c:\Qt\4.3.0rc1\include\QtXml" -I"c:\Qt\4.3.0
rc1\include" -I"." -I"c:\Qt\4.3.0rc1\include\ActiveQt" -I"debug" -I"." -I"c:\Qt\
4.3.0rc1\mkspecs\default" -Fodebug\ @D:\DOCUME~1\Marcel\LOCALS~1\Temp\nm783.tmp
moc_glwidget.cpp
moc_graphicsobject.cpp
moc_layout.cpp
moc_widget.cpp
Generating Code...
link /LIBPATH:"c:\Qt\4.3.0rc1\lib" /NOLOGO /DEBUG /DLL /OUT:debug\calina
.dll @D:\DOCUME~1\Marcel\LOCALS~1\Temp\nm784.tmp
Creating library debug\calina.lib and object debug\calina.exp

D:\Documents and Settings\Marcel\Desktop\calina\calina\calina>