Keyboard short cut for "Next Fuzzy/Untranslated" (alt-PgDn) and "Previous Fuzzy/Untranslated" (alt-PgUp) work as if what we press is "Next Entry" or "Previous Entry"

Version-Release number of selected component (if applicable):
Zanata version 1.6.0-alpha-1 (20120419-0011).

How reproducible:
Always

Steps to Reproduce:
1. Find a document that is multiple-paged contains empty, fuzzy, and approved
translation
   Or find a related empty document, with 
   1, 2 and last entries are approved
   3, 5 entries are fuzzy
   the rest are empty.
2. Uncheck all the Message Filters (or Check all the Message Filters)
3. Click on the entry that below an Approved entry
4. Press Alt-PgUp (Keyboard shortcut of Previous Fuzzy/Untranslated"
  
Actual results:
Cursor move to Approved 

Expected results:
Cursor either move to previous Fuzzy/Untranslated entry, or stay at the current entry if no previous Fuzzy/Untranslated entry

Additional info:
"Next Fuzzy/Untranslated" and "Previous Fuzzy/Untranslated" buttons on the top works