[TYPO3-commerce] problems with navigation

[Alexander]

Hello list
I have a problem. I installed last version of commerce extension and 
created some categories and products. When i click on some entry in a 
category menu i get this message:

Warning: Invalid argument supplied for foreach() in 
........typo3conf/ext/commerce/lib/class.tx_commerce_navigation.php on 
line 204

Warning: Cannot modify header information - headers already sent by 
(output started at 
.....typo3conf/ext/commerce/lib/class.tx_commerce_navigation.php:204) in 
......typo3/sysext/cms/tslib/class.tslib_fe.php on line 2898



---------------------------------
menu TS:

subparts.shopnav = HMENU
subparts.shopnav {
special = userfunction
special.userFunc = user_tx_commerce_catmenu_pub->init
special{
category = 2
showProducts = 0
overridePid = 5
}
1 = TMENU
1 {
wrap = <ul>|</ul>
expAll = 0
noBlur = 1
NO.wrapItemAndSub = <li>|</li>
}
2 < .1
3 < .2

1.itemArrayProcFunc = user_tx_commerce_catmenu_pub->clear
2.itemArrayProcFunc = user_tx_commerce_catmenu_pub->clear
3.itemArrayProcFunc = user_tx_commerce_catmenu_pub->clear
}
--------------------------------------

how to fix it?