sending iCal event to another mobile me user

[sspm]

I've been trying to send iCal events using my iCal/mobile me account to another mobile me user.
the receiver said the iCal format was wrong and couldn't open it in his iphone

does anyone know how to work this thing out
many thanks

[cyclingplatypus]

That's an odd one, might be better to send the email to his Mac and add it to iCal that way...you'd think that it would open up on the iPhone but when I click on it it just zooms.