Reason could be that both had the same surname. And maybe even the same first initial of their first names.
But in any case, similar surnames could be the reason.
Buy when you flew... didn't your friend check to see what FF number was on his boarding pass?
On another note... if the travel agent was using SABRE, and the first name is different, the CRS will reject it automatically. Basically unless your FF# has only surnames and initials, the systems (all carriers except BA and QF ) will accept the number.
[This message has been edited by Guy Betsy (edited 06-14-2003).]