[Localization] Czech, Ukrainian errors on Pootle: 'NoneType' object has no attribute 'split'

[Evelyn Eastmond]

Hello Everyone,

I have a couple of Scratch translators who have had issues with the OLPC 
Pootle server.
Does anyone know what the problem may be?
Here are their error reports:

 From the Czech translator:
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I met strange errors on dev.laptop.org server:

- being not logged in, I can browse the czech Scratch text OK.
- beig logged in (name: karel1), without setting option to "Czech",
  i can download latest already translated (czech) .po file
- whenever I set "Czech" on /translate/home/options.html,
  my /translate/home/ page produces this error:
'NoneType' object has no attribute 'split'

Than I have no "My account" link working to choose from,
 so I must "jump" to 
         options.html
 manually.
Setting other languages goes OK, without error mentioned,
but I like to translate Czech...

Even worse, the same error appears, when I desided to "jump"
        /translate/cs/scratch/Scratch.po?translate=1&view=1
manually. (Similar URL /de/ works well.)
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