[cisco-voip] CUCM: End-of-Life & End-of-sale policies

[al]

Hello,

For a client, I am trying to sum up the End-of-Life and End-of-sale 
policies for CallManager 4.1.3 , 5.1 and 6.1.
First of all, I read the End-of-life Policy: 
http://www.cisco.com/en/US/products/products_end-of-life_policy.html.
Next, I read the End-of-Life and End-of-sales Notices: 
http://www.cisco.com/en/US/products/sw/voicesw/ps556/prod_eol_notices_list.html.

But, there is something, that I don't really understand:

If I want to buy one of the three version (4.1.3,  5.1, 6.1) next month:
For, 4.1.3 and 4.2 : End of sale date: 15 May 2008; End of Software 
Maintenance 15 May 2009, Last date of support:15 May 2011.

For, 5.1 and 6.1, I have to buy the latest "DL380-G5" with one of these 
Cisco Part Number "CM6.0-K9-380G5" or "CM5.1-K9-380G5".
So, the end of life announcement has not yet  released (if I am not 
wrong), can I claim that the end of support would not be before April 
2013 ? (at least five years of support ?)

If you'are wondering about the 4.1.3 choice => It's only about reducing 
the bill (4.1.3 it's the last version not performing the hardware 
verification, so the client has not to buy hardware and keep the 
previous one)

I really prefer the 5.1 or 6.1 choice. (what do you think ?)

Thanks in advance for any support.