correctly detect missing gtkpell module

src/chat_control.py

@@ -78,7 +78,7 @@ from command_system.implementation.execute import Execute, Show
 try:
     import gtkspell
     HAS_GTK_SPELL = True
-except ImportError:
+except (ImportError, ValueError):
     HAS_GTK_SPELL = False
 
 from common import dbus_support

src/config.py

@@ -52,7 +52,7 @@ import profile_window
 try:
     import gtkspell
     HAS_GTK_SPELL = True
-except ImportError:
+except (ImportError, ValueError):
     HAS_GTK_SPELL = False
 
 from common import helpers

src/dialogs.py

@@ -52,7 +52,7 @@ from common import ged
 try:
     import gtkspell
     HAS_GTK_SPELL = True
-except ImportError:
+except (ImportError, ValueError):
     HAS_GTK_SPELL = False
 
 # those imports are not used in this file, but in files that 'import dialogs'