Don't support wireless networks with '\x00' in the ESSID

wicd/wnettools.py

@@ -1251,6 +1251,12 @@ class BaseWirelessInterface(BaseInterface):
         except (UnicodeDecodeError, UnicodeEncodeError):
             print 'Unicode problem with current network essid, ignoring!!'
             return None
+
+        # We (well, DBus) don't support ESSIDs with null bytes in it.
+        # Substitute the byte for use everywhere, so that the UIs know
+        # what to disable.
+        ap['essid'].replace('\x00', '<NULL>')
+
         if ap['essid'] in ['Hidden', '<hidden>', "", None]:
             print 'hidden'
             ap['hidden'] = True