We're seeing more complaints like this:
A user was invited to a meeting but the meeting is showing on her calendar with her as the organizer when in fact the organizer is someone else.
Users may unexpectedly become the organizer for a meeting that they were invited to. This does not change the meeting for all attendees, only the affected person. However, if the user deletes the meeting, it will be cancelled/deleted for all attendees.
This is the result of using Exchange Active Sync to sync an Exchange Server 2007 mailbox with an iPhone, iPad, or Android device and accepting the meeting on the device.
Microsoft has this issue documented in You are incorrectly displayed as a meeting organizer after you synchronize the meeting by using your mobile device in an Exchange Server 2007 environment Knowledge Base article and this issue was first addressed in Rollup Update 4 for Exchange Server 2007 Service Pack 3 and is included in all later Rollups.
Note that the update will not fix corrupt meetings. If you need to fix the organizer, you will need to delete the damaged meeting from the affected user's calendar, and patch the Exchange Server 2007 to prevent future issues. The organizer will need to recreate the meeting.
How to Obtain the Latest Service Pack or Update Rollup for Exchange 2007 Links to all Exchange Server 2007 update rollups and service packs. (Technet)
Current issues with Microsoft Exchange ActiveSync and Third Party Devices (MSKB)
A script to troubleshoot issues with Exchange ActiveSync (TechNet - Exchange blog)
iPhone and the Meeting Request Bug