No one else is getting my alerts on my shared calendar.

I work in a small office and we all share a work iCal. I constantly set up alerts for meetings, conference calls, etc. but no one else ever seems to get my alerts. However, these alerts appear for me, and me alone. It is the same with everyone else in my office. They recieve their own alerts and nothing more.

I have a 13" Macbook Pro, and the other computers are all Macbooks of varying age and size. Mine is just the newest. We all operate on Lion at the moment.

I've tried my hardest to troubleshoot, and I'm at my wit's end. Can anyone help? Is anyone having the same issues?

Thanks!