Serial Numbers/IMEI in user agents?

“Recently” Vodafone has begun to force the user agent “format” to manufacturers producing device that will be sold as “VodafoneLive” devices. These devices follow a standard scheme for the user agent string.
Sample agent: “Vodafone/1.0/V802SE/SEJ001 Browser/SEMC-Browser/4.1 Profile/MIDP-2.0 Configuration/CLDC-1.1″.
As you can see we have the string “Vodafone”, then we have “1.0” (Vodafone specs version 1.0?), then V802SE (V802 from SonyEricsson), SEJ001 (SonyEricsson J001, it’s the firmware version) and then a string that can be customized by each manufacturer, in this case we have the SE browser version (4.1) and the j2me profiles supported.
On one side this can be good for the device detection, we know for sure that all devices with a user agent starting with “Vodafone/1.0″ will be xHTML and have some basic feature (that I haven’t discovered, yet). On the other side some devices might be matched with a wrong device. This doesn’t make a big difference with regard to the markup (xHTML is always xHTML), but might make a difference when delivering contents.

Unfortunately, it seems that this rule was not so clear to manufacturers. Here are a couple of user agents that make an exception:
Vodafone/SonyEricssonV800/R1S025 Browser/SEMC-Browser/4.1 Profile/MIDP-2.0 Configuration/CLDC-1.1
Vodafone/R4.5/SEMC_v800/EU_1 SonyEricssonV800/R1A Browser/SEMC-Browser/4.1 Profile/MIDP-2.0 Configuration/CLDC-1.1
Vodafone/1.0/V902SH/SHG001/SN350257000024598 Browser/UP.Browser/7.0.2.1 Profile/MIDP-2.0 Configuration/CLDC-1.1 Ext-J-Profile/JSCL-1.2.2 Ext-V-Profile/VSCL-2.0.0
Vodafone/1.0/V702NK/NKJ001/IMEI/SN354350000005026 Series60/2.6 Nokia6630/2.39.126 Profile/MIDP-2.0 Configuration/CLDC-1.1

While the first two user agents don’t respect the standard precisely, they still look “OK”, to me (but I don’t know the *real* standard, nobody asked my opinion or shared any official docs with me), but look at the last two. They are presenting the serial number that is to say the IMEI of the device. YES, they are printing the IMEI of the phone in the user agent.

WURFL is not going to list all these user agents, we’d have a ‘device’ for every phone sold around the world. It is strange to see this info in the user agent.
Could this be of any use? Is this against my privacy? Would a user be happy to see his IMEI distributed? Is the IMEI a reserved information? Does this identify a single person?