Border dissapear when layout width set to 100% [SOLVED]

[aswzen]

see this fiddle: http://jsfiddle.net/2jrcmeqm/  and try to collapse the west region

I want to make the west region expanded with 100% width so the entire center region hidden.
But when i collapse the west region, i see there are no border on the right side of the center region.
btw: i see the center region width is larger than the layout parent itself

How to get rid of this?

Thank you in advance..

[jarry]

Please set the 'minWidth' property to 0 for the 'center' panel. The updated example works fine.

http://jsfiddle.net/2jrcmeqm/1/