Mozilla Archive Format, with MHT and Faithful Save

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wót TamerX5 dnja Awg. 1, 2009 · trajny wótkaz

There is a problem in the new version 0.13.4
I can't open any saved pages with the ext. ".MHT", even the old saved ones by previous versions or even the pages saved by internet explorer 6. it show a blank page named "untitled". The only pages I can open are those with ".HTM" extension.
I'm using Firefox 3.5.1, windows XP SP2.
Thanks..