Need explication about rfc2426

Hello,

i'm working on a gnustep (http://www.gnustep.org) application, an 
addressbook. So the first format that i want to support is the 
vcard3.0 (rfc2426). So i've read the rfc and i've some questions :-)

If i understood the concept, a vcard is used to represent a person ; 
so there is many fields to do that (name, birthday, address, 
organization, etc). But can we have more than one N field in the same 
vcard (for the same language) ?

About the UID field ; extract from rfc2426, p24, paragraph 3.6.7:
"The type can include the type parameter "TYPE" to specify the 
format of the identifier. The TYPE parameter value should be an IANA 
registered identifier format. The value can also be a non-standard 
format."
The BNF grammar, that can we find at the end of the rfc, says at the
page 35:
"For name="UID"
param = ""
   ; No parameters allowed
value = text-value"
So, can we have a TYPE parameter or can't we ? :-) Can you give me 
an example of this TYPE parameter ?
More important, is there a standard way (or a very used way) to 
generate this UID ? Should i use the Message-ID way (rfc2822) ?

Regards,

Vincent Ricard

-- 
Vincent