Drupal navigation-menu can not be updated!

Any idea why nothing changed after updating weight in navigation-menu? It works when I try it individually using menu-point... >> edit and change weight-number. But when I change weight under "admin/build/menu-customize/navigation" , a message like "* Changes made in this table will not be saved until the form is submitted." appears above submit button. Than I click on "save configuration" button but nothing changed. Any idea? It is Drupal 6.10. Menu elements are like below:

Blogs	

My blog	

Books (disabled)	

Catalog (disabled)	

Compose tips (disabled)	

Contact (disabled)	

Friend Feed	

Guestbooks	

Mass Contact (disabled)	

Messages	

My account	

My bookmarks	

Oneway management	

Polls (disabled)	

Search (disabled)	

Send an e-Postcard	

Site guestbook	

Tags (disabled)	

Tickets	

Search	

Twoway management	

Twoway received	

Twoway send	

User list	

Users by points	

Wish lists	

Workflow summary	

Create content	

Advertisement	

 
HTML ad	

 
Image ad	


Album	

Blog entry	

Book page	

Forum topic	

Historical event	

Image	

Multi-Choice Question	

Page	

Poll	

Product	

Quiz	

Story	

Web Links for Developers	

Wishlist	

Recent posts	

Feed aggregator	

Sources	

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