[SQLObject] "classes already in register" with Spyder

This probably has more to do with the IDE I'm just trying out (Spyder - 
http://code.google.com/p/spyderlib/) rather than code errors as I 
haven't experienced it before, but still, if anyway to prevent this 
error comes to mind, I'd be glad to hear it.

The first 'runfile' line below represents my application happily running 
through Spyder. But after I close the application and run it for a 
second time, python complains that my sqlobject classes are still in the 
registry. Is there a way to ensure that this registry is clear once my 
application is closed? This isn't really an issue when I'm running the 
application on its own, but it is a pain while trying to edit it.

Best regards,
Tim

Python 2.7 (r27:82525, Jul  4 2010, 09:01:59) [MSC v.1500 32 bit 
(Intel)] on win32
Type "copyright", "credits" or "license" for more information.
 >>> runfile(r'C:\DicSL\dicsl\dicsl.py', wdir=r'C:\DicSL\dicsl')
 >>> runfile(r'C:\DicSL\dicsl\dicsl.py', wdir=r'C:\DicSL\dicsl')
UMD has deleted: gui.video_selection_window, dictionary.dicsl_meta, gui, 
cfg, gui.photo_popup, gui.dialogs.opendictionary, 
dictionary.explanatory, gui.dialogs.explanatory_dialogs, 
gui.gloss_search_panel, gui.usage_window, dictionary.citation, 
dictionary, gui.dialogs.about, error_logging, gui.video_panel, 
gui.component_panel, dictionary.sentence, gui.mplayer_ctrl, 
dictionary.gloss, gui.EnhancedStatusBar, gui.component_descriptions, 
dictionary.component, gui.component_drop_panel, 
gui.playback_rate_slider, dictionary.signentry, dictionary.dialect, 
gui.mainframe, gui.location_panel, gui.component_type, 
gui.dialogs.duplicatefile, gui.dialogs.newdictionary, dictionary.editor, 
dictionary.lang_name, gui.dialogs.dialect_list, gui.dialogs
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
   File 
"C:\Python27\lib\site-packages\spyderlib\widgets\externalshell\startup.py", 
line 122, in runfile
     execfile(filename, glbs)
   File "C:\DicSL\dicsl\dicsl.py", line 11, in <module>
     from gui import mainframe
   File "gui\mainframe.py", line 22, in <module>
     from dictionary.editor import Editor as DictionaryEditor
   File "dictionary\editor.py", line 17, in <module>
     from signentry import SignEntry, SignEntryUpdate
   File "dictionary\signentry.py", line 46, in <module>
     class SignEntry(SQLObject):
   File 
"C:\Python27\lib\site-packages\sqlobject-1.1.1-py2.7.egg\sqlobject\declarative.py", 
line 92, in __new__
     cls.__classinit__(cls, new_attrs)
   File 
"C:\Python27\lib\site-packages\sqlobject-1.1.1-py2.7.egg\sqlobject\main.py", 
line 813, in __classinit__
     classregistry.registry(sqlmeta.registry).addClass(cls)
   File 
"C:\Python27\lib\site-packages\sqlobject-1.1.1-py2.7.egg\sqlobject\classregistry.py", 
line 91, in addClass
     '__file__', '(unknown)')))
ValueError: class SignEntry is already in the registry (other class is 
<class 'dictionary.signentry.SignEntry'>, from the module 
dictionary.signentry in dictionary\signentry.pyc; attempted new class is 
<class 'dictionary.signentry.SignEntry'>, from the module 
dictionary.signentry in dictionary\signentry.pyc)