glade menubar problem

[hardded <hardded pchome com tw>]

Hello, 
I'm new to gtk&glade,

I create a window and put a menubar on it,
but the size of menubar is too big,
I don't know how to resize..

can you help me?? thanks in advance.

my problem in a picture..
http://home.pchome.com.tw/todo/hardded/linux/menubar2big.jpg