C18XMEN?!

Let's see... I collected X-Men comics for about 160 issues, surely I can come up with the first 18 members:

1. Angel
2. Beast
3. Marvel Girl
4. Cyclops
5. Iceman
6. Mimic
7. Havok
8. Polaris
9. Colossus
10. Nightcrawler
11. Storm
12. Thunderbird
13. Banshee
14. Sunfire
15. Wolverine
16. Rogue
17. Phoenix
18. Kitty Pryde
    

I wonder if anyone at IBM ever thought that there might be comic geeks out there that would take a part number to extremes? So what is C18XMEN, besides the only IBM part number I will ever remember?

IBM Lotus Notes, Designer and Administrator 8.0.1 Clients basic configuration for Windows XP and Vista English(C18XMEN)