Meeting invites not showing up when sent via BIS

[Sashko]

I've been setting up events with one of my contacts by sending meeting invites using my calendar on my BB associated to my Gmail account via BIS for the longest time. Recently, I stopped receiving the meeting invites sent to my Gmail account, and now the person I'm sending them to isn't receiving them anymore either (neither through her Gmail account nor via her BlackBerry.net one). We're both with Rogers, and I have a 9780 (although the issue began on my 9700 before my recent upgrade) while she has a Pearl 3G 9100, and I'm on a BES while she is not. Any ideas as to what might be going on?

EDIT: I also tried sending inviting my blackberry.net e-mail account as a participant of the calendar event (so from Gmail to my BB.net address), however I never received it either. I'm suspecting it's getting lost somewhere along the way in the BIS, but am not sure :-/