cannot connect to "shared" 802.11b AP

[chimpsky]

I'm using an orinoco card that works just fine when connecting to my wireless router when the router is set to "open authentication" but I would like to have it set to "shared". I'm using iwconfig and i have no problem setting the essid, mode, and key (with the restricted option added to the key) but when i run a dhcpcd eth1 to optain the dhcp info from the router it takes about 1-2 min then gives me a prompt and the card is stopped (lights turn off). I have spent a lot of time trying to figure this out so i assume the card just doesnt support shared mode??? has anybody else had this problem?
any advise would be helpfull
thanks

[UberLord]

Open is more secure than shared - why do you want to change?

And you're right - some drivers just don't support shared

[chimpsky]

I wanted to change to 'shared' because I wanted to force anyone connecting to the AP to be authenticated. I am under the impression that open allows anyone to connect without authentication and that shared authenticated users based on the wep key. Am I wrong? I know there are a number of flaws with wep but I would like to try and keep out the casual neighbor from getting on my network (something a little more than not broadcasting the ssid). Also, the orinoco card I am using will connect to the AP under windows so I assume no firmware will need to be upgraded this looks like an issue with the linux driver I'm using, right? Either way, I'm curious why open is considered to be more secure than shared.